400 InvalidToken! invalid_grant when fetching new token


Recently, we noticed that we have been getting some 400 errors with the response

“reason”: “Invalid Token!”,
“error”: “invalid_grant”

when we are trying to get a new OAuth token via /oauth/token for users using our Zoom App. Our Zoom App has been live for over a year, and in the last 3 months we have seen rare, but still recurring issues with this. Furthermore, it has been consistently happening to users internal to our company at a much more frequent rate. Any help/guidance/investigation into this issue would be greatly appreciated.

Is this happening for one app or all apps?

This is happening just for one of our apps.

This is still happening, do you have any guidance on this issue?

Can you send me the details of the app in DM?