Why can't I delete my photos?

[AC Question]

I have a samsung Galazy s5 with an sd card installed. Since I'm running out of space on said card, I've been trying to delete photos from the card, but none will stay deleted. I've tried deleting through the built in file manager, the gallery, and even connected it to my laptop and tried to delete them through there. In all cases, the photos simply reappear in a minute or so. The photos were taken with the stock camera app.

 

[B. Diddy]

Welcome to Android Central! Where are you seeing them disappear? Are the files actually reappearing in the SD card's directory, if you're looking there using My Files? Or are you seeing them in your Gallery or Google Photos app? Do you know if those photos were backed up to your Google Photos in the cloud, or some other cloud storage?