Floor tiles lifted

[JK0]

I have a ground floor flat in a modern block built in 2004. This has all concrete floors.

Recently I have noticed the ceramic floor tiles in the bathroom were moving when I walked on them. Today I have scraped out the grout, and the tiles came straight up without difficulty. They have a very solid bed of adhesive on the back of all the tiles, but none stuck to the floor.

I think they must have laid these tiles before the concrete/ screed was properly dry. If possible, I would wish to re-lay these tiles, but I wish them to stay stuck down this time.

Anyone any suggestions regarding adhesive?

[Interlaken]

Your theory could be correct but I always suspect damp in these situations.

I would clean off tiles and concrete with scraper and stick down with Pink Grip - sticks more or less anything - I have used it in countless situations in and out. Get the one with solvent. Available Toolstation.com and very reasonably priced.