Failed mail delivery

Hi,
I set everything with SMTP and in Google cloud console with app registration, published the app and created OAuth 2.0 Client IDs. Everything worked fine until 3 days ago when one of the workers tried to connect an additional mail to the Google calendar in Amelia app.

Since then mails fail to be delivered. And we get this message:
{ “error”: { “code”: 401, “message”: “Request is missing required authentication credential. Expected OAuth 2 access token, login cookie or other valid authentication credential. See https://developers.google.com/identity/sign-in/web/devconsole-project.”, “errors”: [ { “message”: “Login Required.”, “domain”: “global”, “reason”: “required”, “location”: “Authorization”, “locationType”: “header” } ], “status”: “UNAUTHENTICATED”, “details”: [ { “@type”: “type.googleapis.com/google.rpc.ErrorInfo”, “reason”: “CREDENTIALS_MISSING”, “domain”: “googleapis.com”, “metadata”: { “service”: “gmail.googleapis.com”, “method”: “caribou.api.proto.MailboxService.SendMessage” } } ] } }

I have no idea what happened and can’t find the solution. Please help if u can 🙂

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