api error: The user does not exist

when I use the API to create a meeting I receive this error:  {“code”:1001,“message”:“User does not exist: *******”} the procedure is correct, because with another of our accounts it works fine. But only with one, in the other four that we have it gives the indicated error. I also tried to replace the email with the account ID but it still doesn't find it. Can you tell me if I need to configure something myself or if there is a system update problem? I would like to point out that the problem occurred after the migration from the old jwt authentication system to the new OAuth