I'd like to take a deeper look into this for you. Would you be able to provide more context on the following points:
What is your store URL?
Do you have a screenshot of the error message the customer sees when redirected back to Shopify?
Has this been a new issue or have your customers always been redirected to the error page since using PayFast?
Is there any further details you can provide from the abandoned cart itself?
How many related abandoned carts do you have?
Thank you and I look forward to your reply.
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