Hopefully someone can help! As is so often the case I guess; I'm looking after the problem has arisen as opposed to checking first , we've laid tiles onto a ply floor previously without an issue but this time the adhesive won't set. We used a wickes flexible ceramic tile/quarry tile adhesive suitable for wood flooring, the tiles are marble. They've been down more than 24 hours and they are showing no sign of setting, and even more irritatingly one has now cracked. Please can anyone advise?
Many thanks in advance!