matt tiles

just having my bathroom tiled at the moment with large matt white tiles!
about 3 hrs or so after the tiler had left, the adhesive seems to be soaking through the tiles.(look like huge grease marks).
The tiler used Dunlop pro fix 4 adhesive which he says he`s used for years.Any advice would be welcolme!

what type of tile is it ceramic, porcelain, marble, slate ect. did you notice what trowel he used and what background did he tile to ?

Thanks for the reply.
The tiles are ceramic low level matt(white) floor tiles.which I was told would be no prob. applying to a wall as well.
The trowel (v.limited knowledge here!) was a large cerated one with handle on top.
It looks like the adhesive has been dotted on as the marks have come through as large circles.
The surface(s) were a plasterboard wall & a wooden (plywood stud wall).
Thanks again . Steve.