Not redirecting to success page

Hi,

Our website suddenly stops redirecting to thank you page anymore which was previously working and I didn’t changed anything on the Settings. The website is not live yet and I’m using a paypal sandbox account. Don’t know what went wrong. Below is the paypal-api.log.

LOG ENTRY: Tue Mar 6th, 2018 @ precisely 3:35 am UTC
PHP v7.0.27 :: WordPress v4.9 :: s2Member v170722 :: s2Member Pro v170722
Memory 10.90 MB :: Real Memory 14.00 MB :: Peak Memory 11.80 MB :: Real Peak Memory 14.00 MB
waecssa-web.swishclients.com.au/s2-full-member-one-time/
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.167 Safari/537.36
-------- Input vars: ( Tue Mar 6, 2018 3:35:10 am UTC ) --------
array (
  'METHOD' => 'SetExpressCheckout',
  'RETURNURL' => 'http://waecssa-web.swishclients.com.au/s2-full-member-one-time/?s2p-option&s2member_paypal_xco=s2member_pro_paypal_checkout_return',
  'CANCELURL' => 'http://waecssa-web.swishclients.com.au/s2-full-member-one-time/?s2p-option&s2member_paypal_xco=s2member_pro_paypal_checkout_cancel',
  'PAGESTYLE' => 'paypal',
  'LOCALECODE' => '',
  'NOSHIPPING' => '1',
  'SOLUTIONTYPE' => 'Sole',
  'LANDINGPAGE' => 'Billing',
  'ALLOWNOTE' => '0',
  'PAYMENTREQUEST_0_PAYMENTACTION' => 'Sale',
  'MAXAMT' => '75.00',
  'PAYMENTREQUEST_0_DESC' => 'Full Member $75 USD / One Time (for 1 year access, non-re...',
  'PAYMENTREQUEST_0_CUSTOM' => 'waecssa-web.swishclients.com.au',
  'PAYMENTREQUEST_0_CURRENCYCODE' => 'USD',
  'PAYMENTREQUEST_0_ITEMAMT' => '75.00',
  'PAYMENTREQUEST_0_TAXAMT' => '0.00',
  'PAYMENTREQUEST_0_AMT' => '75.00',
  'L_PAYMENTREQUEST_0_QTY0' => '1',
  'L_PAYMENTREQUEST_0_NAME0' => 'Full Member $75 USD / One Time (for 1 year access, non-recurring, no trial)',
  'L_PAYMENTREQUEST_0_NUMBER0' => '2::1 Y',
  'L_PAYMENTREQUEST_0_AMT0' => '75.00',
  'PAYMENTREQUEST_0_SHIPTONAME' => 'Jerick Dimaano',
  'PAYMENTREQUEST_0_SHIPTOSTREET' => '',
  'PAYMENTREQUEST_0_SHIPTOCITY' => '',
  'PAYMENTREQUEST_0_SHIPTOSTATE' => '',
  'PAYMENTREQUEST_0_SHIPTOCOUNTRYCODE' => 'US',
  'PAYMENTREQUEST_0_SHIPTOZIP' => '',
  'EMAIL' => 'jerickallan24@gmail.com',
  'VERSION' => '71.0',
  'USER' => 'jerick.swishdesign-facilitator_api1.gmail.com',
  'PWD' => 'xxxxxxxx/PWD/SIG',
  'SIGNATURE' => 'xxxxxxxx/PWD/SIG',
)
-------- Output string/vars: ( Tue Mar 6, 2018 3:35:12 am UTC ) --------
TOKEN=EC%2d6DB56662K42699236&TIMESTAMP=2018%2d03%2d06T03%3a35%3a12Z&CORRELATIONID=7b487ceccb11a&ACK=Success&VERSION=71%2e0&BUILD=43715881
array (
  'TOKEN' => 'EC-6DB56662K42699236',
  'TIMESTAMP' => '2018-03-06T03:35:12Z',
  'CORRELATIONID' => '7b487ceccb11a',
  'ACK' => 'Success',
  'VERSION' => '71.0',
  'BUILD' => '43715881',
)

LOG ENTRY: Tue Mar 6th, 2018 @ precisely 3:36 am UTC
PHP v7.0.27 :: WordPress v4.9 :: s2Member v170722 :: s2Member Pro v170722
Memory 10.89 MB :: Real Memory 14.00 MB :: Peak Memory 11.77 MB :: Real Peak Memory 14.00 MB
waecssa-web.swishclients.com.au/s2-full-member-one-time/?s2p-option&s2member_paypal_xco=s2member_pro_paypal_checkout_return&token=EC-6DB56662K42699236&PayerID=CCC4XZKWJGAFQ
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.167 Safari/537.36
-------- Input vars: ( Tue Mar 6, 2018 3:36:04 am UTC ) --------
array (
  'METHOD' => 'GetExpressCheckoutDetails',
  'TOKEN' => 'EC-6DB56662K42699236',
  'VERSION' => '71.0',
  'USER' => 'jerick.swishdesign-facilitator_api1.gmail.com',
  'PWD' => 'xxxxxxxx/PWD/SIG',
  'SIGNATURE' => 'xxxxxxxx/PWD/SIG',
)
-------- Output string/vars: ( Tue Mar 6, 2018 3:36:06 am UTC ) --------
TOKEN=EC%2d6DB56662K42699236&BILLINGAGREEMENTACCEPTEDSTATUS=0&CHECKOUTSTATUS=PaymentActionNotInitiated&TIMESTAMP=2018%2d03%2d06T03%3a36%3a06Z&CORRELATIONID=aa32b93711b6c&ACK=Success&VERSION=71%2e0&BUILD=43715881&EMAIL=jerick%2eswishdesign%2dbuyer%40gmail%2ecom&PAYERID=CCC4XZKWJGAFQ&PAYERSTATUS=verified&FIRSTNAME=test&LASTNAME=buyer&COUNTRYCODE=US&ADDRESSSTATUS=Confirmed&CURRENCYCODE=USD&AMT=75%2e00&ITEMAMT=75%2e00&SHIPPINGAMT=0%2e00&HANDLINGAMT=0%2e00&TAXAMT=0%2e00&CUSTOM=waecssa%2dweb%2eswishclients%2ecom%2eau&DESC=Full%20Member%20%2475%20USD%20%2f%20One%20Time%20%28for%201%20year%20access%2c%20non%2dre%2e%2e%2e&INSURANCEAMT=0%2e00&SHIPDISCAMT=0%2e00&INSURANCEOPTIONOFFERED=false&L_NAME0=Full%20Member%20%2475%20USD%20%2f%20One%20Time%20%28for%201%20year%20access%2c%20non%2drecurring%2c%20no%20trial%29&L_NUMBER0=2%3a%3a1%20Y&L_QTY0=1&L_TAXAMT0=0%2e00&L_AMT0=75%2e00&PAYMENTREQUEST_0_CURRENCYCODE=USD&PAYMENTREQUEST_0_AMT=75%2e00&PAYMENTREQUEST_0_ITEMAMT=75%2e00&PAYMENTREQUEST_0_SHIPPINGAMT=0%2e00&PAYMENTREQUEST_0_HANDLINGAMT=0%2e00&PAYMENTREQUEST_0_TAXAMT=0%2e00&PAYMENTREQUEST_0_CUSTOM=waecssa%2dweb%2eswishclients%2ecom%2eau&PAYMENTREQUEST_0_DESC=Full%20Member%20%2475%20USD%20%2f%20One%20Time%20%28for%201%20year%20access%2c%20non%2dre%2e%2e%2e&PAYMENTREQUEST_0_INSURANCEAMT=0%2e00&PAYMENTREQUEST_0_SHIPDISCAMT=0%2e00&PAYMENTREQUEST_0_SELLERPAYPALACCOUNTID=jerick%2eswishdesign%2dfacilitator%40gmail%2ecom&PAYMENTREQUEST_0_INSURANCEOPTIONOFFERED=false&L_PAYMENTREQUEST_0_NAME0=Full%20Member%20%2475%20USD%20%2f%20One%20Time%20%28for%201%20year%20access%2c%20non%2drecurring%2c%20no%20trial%29&L_PAYMENTREQUEST_0_NUMBER0=2%3a%3a1%20Y&L_PAYMENTREQUEST_0_QTY0=1&L_PAYMENTREQUEST_0_TAXAMT0=0%2e00&L_PAYMENTREQUEST_0_AMT0=75%2e00&PAYMENTREQUESTINFO_0_ERRORCODE=0
array (
  'TOKEN' => 'EC-6DB56662K42699236',
  'BILLINGAGREEMENTACCEPTEDSTATUS' => '0',
  'CHECKOUTSTATUS' => 'PaymentActionNotInitiated',
  'TIMESTAMP' => '2018-03-06T03:36:06Z',
  'CORRELATIONID' => 'aa32b93711b6c',
  'ACK' => 'Success',
  'VERSION' => '71.0',
  'BUILD' => '43715881',
  'EMAIL' => 'jerick.swishdesign-buyer@gmail.com',
  'PAYERID' => 'CCC4XZKWJGAFQ',
  'PAYERSTATUS' => 'verified',
  'FIRSTNAME' => 'test',
  'LASTNAME' => 'buyer',
  'COUNTRYCODE' => 'US',
  'ADDRESSSTATUS' => 'Confirmed',
  'CURRENCYCODE' => 'USD',
  'AMT' => '75.00',
  'ITEMAMT' => '75.00',
  'SHIPPINGAMT' => '0.00',
  'HANDLINGAMT' => '0.00',
  'TAXAMT' => '0.00',
  'CUSTOM' => 'waecssa-web.swishclients.com.au',
  'DESC' => 'Full Member $75 USD / One Time (for 1 year access, non-re...',
  'INSURANCEAMT' => '0.00',
  'SHIPDISCAMT' => '0.00',
  'INSURANCEOPTIONOFFERED' => 'false',
  'L_NAME0' => 'Full Member $75 USD / One Time (for 1 year access, non-recurring, no trial)',
  'L_NUMBER0' => '2::1 Y',
  'L_QTY0' => '1',
  'L_TAXAMT0' => '0.00',
  'L_AMT0' => '75.00',
  'PAYMENTREQUEST_0_CURRENCYCODE' => 'USD',
  'PAYMENTREQUEST_0_AMT' => '75.00',
  'PAYMENTREQUEST_0_ITEMAMT' => '75.00',
  'PAYMENTREQUEST_0_SHIPPINGAMT' => '0.00',
  'PAYMENTREQUEST_0_HANDLINGAMT' => '0.00',
  'PAYMENTREQUEST_0_TAXAMT' => '0.00',
  'PAYMENTREQUEST_0_CUSTOM' => 'waecssa-web.swishclients.com.au',
  'PAYMENTREQUEST_0_DESC' => 'Full Member $75 USD / One Time (for 1 year access, non-re...',
  'PAYMENTREQUEST_0_INSURANCEAMT' => '0.00',
  'PAYMENTREQUEST_0_SHIPDISCAMT' => '0.00',
  'PAYMENTREQUEST_0_SELLERPAYPALACCOUNTID' => 'jerick.swishdesign-facilitator@gmail.com',
  'PAYMENTREQUEST_0_INSURANCEOPTIONOFFERED' => 'false',
  'L_PAYMENTREQUEST_0_NAME0' => 'Full Member $75 USD / One Time (for 1 year access, non-recurring, no trial)',
  'L_PAYMENTREQUEST_0_NUMBER0' => '2::1 Y',
  'L_PAYMENTREQUEST_0_QTY0' => '1',
  'L_PAYMENTREQUEST_0_TAXAMT0' => '0.00',
  'L_PAYMENTREQUEST_0_AMT0' => '75.00',
  'PAYMENTREQUESTINFO_0_ERRORCODE' => '0',
)

LOG ENTRY: Tue Mar 6th, 2018 @ precisely 3:36 am UTC
PHP v7.0.27 :: WordPress v4.9 :: s2Member v170722 :: s2Member Pro v170722
Memory 10.90 MB :: Real Memory 14.00 MB :: Peak Memory 11.77 MB :: Real Peak Memory 14.00 MB
waecssa-web.swishclients.com.au/s2-full-member-one-time/?s2p-option&s2member_paypal_xco=s2member_pro_paypal_checkout_return&token=EC-6DB56662K42699236&PayerID=CCC4XZKWJGAFQ
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.167 Safari/537.36
-------- Input vars: ( Tue Mar 6, 2018 3:36:06 am UTC ) --------
array (
  'METHOD' => 'DoExpressCheckoutPayment',
  'TOKEN' => 'EC-6DB56662K42699236',
  'PAYERID' => 'CCC4XZKWJGAFQ',
  'PAYMENTREQUEST_0_PAYMENTACTION' => 'Sale',
  'PAYMENTREQUEST_0_DESC' => 'Full Member $75 USD / One Time (for 1 year access, non-re...',
  'PAYMENTREQUEST_0_CUSTOM' => 'waecssa-web.swishclients.com.au',
  'PAYMENTREQUEST_0_CURRENCYCODE' => 'USD',
  'PAYMENTREQUEST_0_ITEMAMT' => '75.00',
  'PAYMENTREQUEST_0_TAXAMT' => '0.00',
  'PAYMENTREQUEST_0_AMT' => '75.00',
  'L_PAYMENTREQUEST_0_QTY0' => '1',
  'L_PAYMENTREQUEST_0_NAME0' => 'Full Member $75 USD / One Time (for 1 year access, non-recurring, no trial)',
  'L_PAYMENTREQUEST_0_NUMBER0' => '2::1 Y',
  'L_PAYMENTREQUEST_0_AMT0' => '75.00',
  'VERSION' => '71.0',
  'USER' => 'jerick.swishdesign-facilitator_api1.gmail.com',
  'PWD' => 'xxxxxxxx/PWD/SIG',
  'SIGNATURE' => 'xxxxxxxx/PWD/SIG',
)
-------- Output string/vars: ( Tue Mar 6, 2018 3:36:08 am UTC ) --------
TOKEN=EC%2d6DB56662K42699236&SUCCESSPAGEREDIRECTREQUESTED=false&TIMESTAMP=2018%2d03%2d06T03%3a36%3a08Z&CORRELATIONID=696f4f9a89ec7&ACK=Success&VERSION=71%2e0&BUILD=43715881&INSURANCEOPTIONSELECTED=false&SHIPPINGOPTIONISDEFAULT=false&PAYMENTINFO_0_TRANSACTIONID=92L975166D988515K&PAYMENTINFO_0_TRANSACTIONTYPE=cart&PAYMENTINFO_0_PAYMENTTYPE=instant&PAYMENTINFO_0_ORDERTIME=2018%2d03%2d06T03%3a36%3a08Z&PAYMENTINFO_0_AMT=75%2e00&PAYMENTINFO_0_FEEAMT=2%2e48&PAYMENTINFO_0_TAXAMT=0%2e00&PAYMENTINFO_0_CURRENCYCODE=USD&PAYMENTINFO_0_PAYMENTSTATUS=Completed&PAYMENTINFO_0_PENDINGREASON=None&PAYMENTINFO_0_REASONCODE=None&PAYMENTINFO_0_PROTECTIONELIGIBILITY=Eligible&PAYMENTINFO_0_PROTECTIONELIGIBILITYTYPE=ItemNotReceivedEligible%2cUnauthorizedPaymentEligible&PAYMENTINFO_0_SELLERPAYPALACCOUNTID=jerick%2eswishdesign%2dfacilitator%40gmail%2ecom&PAYMENTINFO_0_SECUREMERCHANTACCOUNTID=48KJPSUBFG8GU&PAYMENTINFO_0_ERRORCODE=0&PAYMENTINFO_0_ACK=Success
array (
  'TOKEN' => 'EC-6DB56662K42699236',
  'SUCCESSPAGEREDIRECTREQUESTED' => 'false',
  'TIMESTAMP' => '2018-03-06T03:36:08Z',
  'CORRELATIONID' => '696f4f9a89ec7',
  'ACK' => 'Success',
  'VERSION' => '71.0',
  'BUILD' => '43715881',
  'INSURANCEOPTIONSELECTED' => 'false',
  'SHIPPINGOPTIONISDEFAULT' => 'false',
  'PAYMENTINFO_0_TRANSACTIONID' => '92L975166D988515K',
  'PAYMENTINFO_0_TRANSACTIONTYPE' => 'cart',
  'PAYMENTINFO_0_PAYMENTTYPE' => 'instant',
  'PAYMENTINFO_0_ORDERTIME' => '2018-03-06T03:36:08Z',
  'PAYMENTINFO_0_AMT' => '75.00',
  'PAYMENTINFO_0_FEEAMT' => '2.48',
  'PAYMENTINFO_0_TAXAMT' => '0.00',
  'PAYMENTINFO_0_CURRENCYCODE' => 'USD',
  'PAYMENTINFO_0_PAYMENTSTATUS' => 'Completed',
  'PAYMENTINFO_0_PENDINGREASON' => 'None',
  'PAYMENTINFO_0_REASONCODE' => 'None',
  'PAYMENTINFO_0_PROTECTIONELIGIBILITY' => 'Eligible',
  'PAYMENTINFO_0_PROTECTIONELIGIBILITYTYPE' => 'ItemNotReceivedEligible,UnauthorizedPaymentEligible',
  'PAYMENTINFO_0_SELLERPAYPALACCOUNTID' => 'jerick.swishdesign-facilitator@gmail.com',
  'PAYMENTINFO_0_SECUREMERCHANTACCOUNTID' => '48KJPSUBFG8GU',
  'PAYMENTINFO_0_ERRORCODE' => '0',
  'PAYMENTINFO_0_ACK' => 'Success',
)

Don’t use Paypal sandbox - it’s buggy…