sshd giving errors: banner line contains invalid characters

[keboose]

Recently, I have started getting SSH login errors, every 48 hours or so these two will show up in my alerts, and clear the next morning:

Code:

Mar 14 04:30:14 NASBox sshd[89935]: error: kex_exchange_identification: client sent invalid protocol identifier "GET http://clientapi.ipip.net/echo.php?info=20200314163014 HTTP/1.1"
Mar 14 04:30:15 NASBox sshd[89937]: error: kex_exchange_identification: banner line contains invalid characters

I don't know what these mean other than that it has to do with the SSH service. From my limited experience, it looks to me like someone is trying to login, and the data packets are not formatted correctly, is that right? I'm not worried about security, as I have root login disabled, and disabled password auth (key only), but can I do something else to mitigate these errors?