Brand new PC...can't play RDR2

[hivesql]

I got a new PC with a RTX 3090. Played Cyberpunk 2077 for a few hours on max settings and everything worked fine. No issues whatsoever.

Install RDR2.....the VULKAN api refuses to let me change resolutions beyond a choice of like 4 resolutions all of which are way too small. I want to play 3840 × 2160 but the max it goes up to is like 1920x1080 or something like that. This means full screen only covers like 1/4 of my large monitor

Change to DX12 api. This lets me go 3840 x 2160 and full screen, however. The game runs for 10 seconds and then always gives me the ERR GFX STATE error. Tried it 8 times. Always same thing.

What is wrong with Rockstar developers? Game came out in 2018, and they still haven't fixed any of this?