Maybe you need to check a few things, I'm just guessing these.
Google is a bit more special when it comes to security features anyway. In the meantime, it is inevitable to store a special release connection for clients that do not have a multiple step confirmation for the first login. As possible years ago, email address and account password no longer works. Google calls this "Your connections to third-party apps and services".
Then, in exchange with Google, check if parameters or sequences for the topics SPF, DKIM, DMARC, DANE, MCP, DNSBL etc. must or can be stored, if available. DNS Health in the Domains section of the Grommunio Admin provides good support for help in this. If you exchange your emails directly with Google, the most important areas should be green there.
In my case, this is not the case with Strato, because I internally go for receiving and sending emails via the Synology Mail-Plusserver and there the above topics are stored and ready for exchange with Strato in my case.
If you go to the individual buttons, the parameters are displayed there, which are then to be deposited with Google if necessary.