I've had this phone for a while now so maybe it's just glitching out and I'm not tech savvy. For the past month every time I delete pictures they usually reappear again within a day. Any idea of what could be happening?
This can be caused by thumbnail files sticking around when they shouldn't, though I can't say if this is the case here. Looks like you aren't the only one having pictures pop back up either. First thing to try would be using the 'clear data' option on the Camera/Gallery app in System Settings > Apps. Right after you clear the data, reboot the phone.