The below error is encounter suddenly to our production and while debugging found the issue related to unathorization.

Error: Failed to acquire token from AAD: {"error":"invalid_grant","error_description":"AADSTS50173: The provided grant has expired due to it being revoked, a fresh auth token is needed. The user might have changed or reset their password.

 Test connection failed. Details: Error from token exchange: Runtime call was blocked because connection has error status: Enabled| Error, and microsoftforms is in the block list. Connection errors: [ParameterName: token, Error: Code: Unauthorized, Message: 'Failed to refresh access token for service: aadcertificate. Correlation Id=956F3FD8-14DB-48B2-8A59-B9E732BB4905, UTC TimeStamp=9/9/2020 2:12:54 PM, Error: Failed to acquire token from AAD: {"error":"invalid_grant","error_description":"AADSTS50173: The provided grant has expired due to it being revoked, a fresh auth token is needed. The user might have changed or reset their password. The grant was issued on '2020-05-21T13:20:41.4577451Z' and the TokensValidFrom date (before which tokens are not valid) for this user is '2020-08-24T18:29:02.0000000Z'. Trace ID: 93c8261e-a4e1-4d18-bac2-ce326c8a2d00 Correlation ID: e5643921-a39c-4216-b2ba-53fb5a80e988 Timestamp: 2020-09-09 14:12:54Z","error_codes":[50173],"timestamp":"2020-09-09 14:12:54Z","trace_id":"93c8261e-a4e1-4d18-bac2-ce326c8a2d00","correlation_id":"e5643921-a39c-4216-b2ba-53fb5a80e988","error_uri":"https://login.windows.net/error?code=50173"}']

We tried authenticating with the same user and it shows success but still getting above error, don’t know if this was some kind of bug but we tried several time and it was same.

Till the time we know, it was due to reset of password that happened last day. at the end we navigated to data -> connections. 

Which was asking to FIX CONNECTION for the user we were trying to authenticate. Click on FIX CONNECTION or Switch Account and it will fix it instantly