Hello,
Thank you for reaching out to us, we are here to help.
This error most likely means that the API credentials are not valid. I suggest disconnecting your account and reconnecting it with the onboarding wizard, as described here: https://woocommerce.com/document/woocommerce-paypal-payments/#connect-paypal-account
In the past, we saw this issue happening before when the user removed the mandatory data from the fields in the checkout page and pays with a vaulted PayPal or ACDC button, API validation message will appear instead of the regular WooCommerce one. We expect that there might be a plugin active that alters the billing fields before they are picked up by our plugin.
?
In order to test this assumption, I would like to ask you to perform conflict testing. Please turn off all other plugins (except WooCommerce and PayPal Payments) and see if this issue can still be reproduced. If this does not give you any results, we would like to take a look at your system report and the logs of the date that this issue occurred. If you don’t feel comfortable sharing those details on a public forum, please open a ticket with our service desk. You can find the instruction for this here: https://paypal.inpsyde.com/docs/request-support/
(please add the URL of this thread in the ticket as well)
Kind regards,
Joost
