Missing Proxies in Final Cut - no transcode possible

I am working on a documentary in final cut. So I have a lot of footage. I tried to create proxies for all of my clips, selecting all events and choose transcode. It rendered all night but in the morning proxies for a
lot of clips are still missing. There is a warning sign next to the
event and the file clips. The files are available when I select show
original but when I try to select the files and click transcode nothing
happens. Is there a way to find out about the problem? Can i see log
files of the transcoding process? How can I see what this warning sign
means? Can I somehow create those proxies without deleting all of the
proxies already created?

Its Final cut 10.5.4. Proxies are missing in some clips in every event. So the codec should not be the problem - Mostly XAVS-S 50Mbit 50p HD.

Can you post a screenshot of the warning sign?

Maybe I have the solution. I shot some of my takes in HLG3 - which is detected a HDR. I have to select a "color space override" in settings to Rec. 709 manually to work with them in SDR - and I think the settings havent been changed in all clips in some events. When I select all events and render proxies I get a warning "some hdr clips will be rendered in ProRes instead of H264" or something similar. I clicked ok and indeed some clips were rendered in ProRes over night when ALL Clips in the event were set to HDR. BUT in one event I think the setting was inconsistent and for some strange reason it only rendered the Rec 709 setting files to H264 and did not render the other files at all. Now I set everything to Rec 709, deleted all prores proxies and try to rerender.

Seemed to work, I think there are no clips offline now. But therefore some Proxies are way too bright and clipping. When I view them in "original" quality with color space override rec 709 they are just fine..