The clue is in that statement “ the tiles are coming off easily) tiler should have done thus in the 1st place. He should not get paid again.. on the + side obviously the contractor can see the errors.Thanks guys, been through it today with primary contractor. Dot and dab tiles all coming off, surface being properly prepared and full bed adhesive for retiling. The upside is we can save the tiles…..they are coming off quickly and easily