Hello. I got this message today. I checked for update and it is say I am up-to-date. Did Microsoft postpone Windows 10 version 2004 because of the current issues got discovered in the last few days? Also, it says my device isn't quite ready for it.
What that message means is that Microsoft hasn't fixed it yet so that that it will be compatible with your device. It is using wording that makes out your device to be the problem - and not them. Typical Microsoft tactic.
Have a look at the known issues. There is something on your device not ready. Great that MS spotted it.
You can check the list here at ask woody:wow.
How do I check which one is not ready in the list?