how do i clean matt tiles

[dazkim]

hello everyone i am new to this
i need some advise on how to clean my matt tiles
i had a new bathroom fitted last week
when they had done fitting the tiles it left a white powdery mark on the tiles where they wiped the walls down
they said it will come off with 2 or 3 more wipe downs with a sponge and water
i have been wiping them down for a week now and they still havent come clean
i feel like pulling my hair out some please help me
is there anything i can spray on them
kim xx

 

[joe-90]

Nip into your local tile shop. They'll have products to remove cement grout.