ACR is opening selected files in batches

Hi! Im trying to figure out the best way to explain this problem because its a litle weird, but here goes.

Heres a hypothetical of a situation that keeps happening- so when i select say, 100 photos from a folder to be opened in ACR, it will only open 75 of those photos. A lot of times i wont notice, will edit, and save, close the window, and then the remaining 25 photos will open in ACR separatedly. Why is this happening? Its affecting my file saving flow and putting all my photos out of order.

The files that open second appear to be random (no star marks, no noticable differences).

how am i able to prevent this?