Nextcloud not recognizing file types

I have I few files of JPGs which I converted from a DSLR RAW file and for some reason with this batch of pictures, Nextcloud is not recognizing them as a type of file it can open and just defaults to downloading. I have many other photos that I can view in Nextcloud that were created with the same method

I’m using Nextcloud 12 on Ubuntu 16.04

Turns out it’s all image types, not just JPG

Okay, I see a bit of what happened, but not what the simple solution is. Nextcloud doesn’t seem to have any idea what my files are at all. I found if I upload the files all over again then it can figure out what it is and we are happy from there. But this would mean I’d have to do this to 100GB of data across the people on my server. Is there a background server-side command that will figure all this stuff out on existing data without me having to rewrite 100GB of information back?

EDIT: Rewriting back the files and having Nextcloud recognize the file types only works SOMETIMES at this point now. It isn’t recognizing a vast majority of my mp3s as mp3s or my pictures as any sort of picture format. I’ve found with weird issues like this there seems to be no answer, so I’m going to wait a bit longer and I suppose backup my data again, wipe my container and rebuild everything from scratch