File too large to proxy?

I've been making proxies for weeks now to send project files over to an editor without needing the original file, I've got 4k camera footage that's an hour and 38 minutes long, it works perfectly fine converting to a proxy but at 50 minutes it just stops and says "failed" it doesn't give any proper errors it just says failed to find a certain frame and it gives the same frame number every time that it stops, every other file in the project proxied just fine I just can't convert this one, could it be too big? Which is kinda annoying considering that's WHY I create proxies in the first place lol (not home right now otherwise I'd post pictures of it too, but that's all the information I get anyways)