Warnings can be ignored for now, but you should address them when you upgrade to next CB version. As per the screenshot devices are showing active. Are they reporting as online and is the MP populating against each entry? Are the clients upgraded as well?
SCCM 2211 issue with Devices
I have upgraded my SCCM Server to 2211, after upgrading I see under Devices all my devices as not contacted.
I have no Idea why?
During the Installation I am getting the following warning