Code break after upgrading API from 2019-09 to the latest

Our API was 40 versions old, so I clicked on the “change version” and selected the latest.
This broke our payment system and I get this error:

{“success”:“no”,“message”:“[HTTP/1.1 400 Bad Request] {\n "message": "Missing parameter client_secret",\n "type": "bad_request.missing_parameter"\n}\n”}

Have you checked the Release notes for any breaking changes for the API call your making? :slightly_smiling_face:

I have upgraded from 40versions ago. So no I have not gone through all of them.
Any help is really appreciated