As has been explained in other threads ... BlackMagic's gen 5 firmware requires a completely different code within any app that tries to read and work with it than the gen 4 did. So Adobe is testing their new code for using it in the public beta, rather than testing in a release version.
Which sounds sensible to me. Most users would rather the shipping verision options were all fully tested out.
You can try working in the public beta, which normally is a very stable program. Or you can revert to gen 4 BlackMagic firmware in your camera for another few weeks. I would guess within a few weeks we'll get the gen 5 code in a shipping version.
As someone who works with and teaches pro colorists, I'm also rather "up" on Resolve and visit and participate in BlackMagic forums both the BM ones and on LGG. There's been some "fun" in Resolve with gen 5 at times for some users also.
Especially for many, it really fouled up their peaking and focus capabilities. An update of the firmware has handled many of the problems, but some users with some lenses are still not able to use the gen 5 code in their camera and get full use of their lenses.
As I've got a couple of the lenses that are still problematic, I've not updated to gen 5 yet on my BMPCC4K.
New stuff isn't always completely issue free, of course.