MyWorks Paypal Module - "Amount is Required" - bug with no reply

[Drecca]

Anyone else having this issue with the MyWorks paypal billing agreements module? Every client on it does not auto-bill on invoice due. The error, when attempting to capture manually, or via the cron is "Amount is Required". Of course, there's an amount there, and even if it shows that error, the invoice will then be processed (when done manually), and the invoice marked as paid a minute later. When there's a Paypal invoice due, the cron does not complete, and CC charges (via Stripe) have to be done manually as well

Their support haven't answered in weeks, so I'm asking if anyone else has come across this. Here's the error from the cron : 

 [ERROR] WHMCS\Exception\Module\NotServicable: Amount is Required in                                                    
 /home/username/public_html/vendor/whmcs/whmcs-foundation/lib/Billing/Invoice.php:0                                      
 Stack trace:                                                                                                           
 #0 /home/username/public_html/includes/ccfunctions.php(0): WHMCS\Billing\Invoice->addPayment(0, '72D22364LP07372...',   
 NULL, 'paypalbilling', true)                                                                                           
 #1 /home/username/public_html/includes/ccfunctions.php(0): captureCCPayment(27984)                                      
 #2 /home/username/public_html/vendor/whmcs/whmcs-foundation/lib/Cron/Task/ProcessCreditCardPayments.php(0):             
 ccProcessing(Object(WHMCS\Cron\Task\ProcessCreditCardPayments))