It's always what's below the tile that's the culprit. Tiles directly on cement typically fail. Same with parquet floor squares. They'll also pop up like your tiles did.

I don't see the usual cement adhesive under these as well. Those tiles also don't look like porcelain and are possibly not even meant for floor use. I can't tell from the picture alone what you've got but there is a range of tiles; they are classified according to their PEI rating. Tiles on the floor should ideally be rated a 4. If you put a membrane underneath the tiles they should hold properly.