I’m trying to integrate Google Wallet into my website. I’m getting the message as below. Does anybody know why this happens? What should I do to resolve this issue? Please help me.
Uh oh. There was a problem.
We couldn't complete your purchase because of a technical issue.
Details of the problem below: Unfortunately, we could not confirm your purchase with the merchant's server. Your order has been canceled. Please contact the merchant if this problem continues.
Getting Postback_error.
First, piece of advice that this community reminds everyone when posting questions (or else your question maybe downvoted or closed by the community).
That out of the way, and assuming you are referring to Wallet for Digital Goods API, the documentation should help guide you to debugging your implementation, which seems to point to an error in your POSTBACK handler:
Important: If you specify a postback URL, your server must respond promptly and correctly to the HTTP POST messages that Google sends for each transaction. Otherwise, the transaction will be canceled.
