Good day @EG-MorningStar,
Thank you for posting to the PayPal community.
Based on the error message, this looks like an issue with your internal website(built via third party platform eCommerce).
Third party platforms eCommerce develops their own plugins/modules.
I suggest to please contact the support of your third party platform(eCommerce) who can able to help you regarding plugins/modules setup.
Note : PayPal system is a payment gateway, which will receive the payment request payload (i.e Payment and Item details, Shipping details, Invoice number, Amount details etc.) from merchant websites(built via third party platforms eCommerce Shopify) and process the payments accordingly.
Merchants should handle their internal website code and pass the appropriate payment API calls to PayPal system.
Sincerely,
Chiranjeevi
PayPal/Braintree MTS
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