Coinbase Fix Api

I successfully established a connection using FIX 4.2 and didn’t encounter any issues. However, when attempting to connect with the latest FIX 5.0 API, I ran into problems. The message for FIX 4.2 is also shorter. Is there a way to retrieve the error message from the logon attempt?

If there is any example message or code for the newest fix 5.0. it would be perfect