Dark grout going white and dark residue on cloth when cleaning

[Zoe1994]

Hi,

We got our bathroom done just over a year ago. The tiler used mapei grout in river grey. I have noticed some of the grout lines turning white and when I try running it off I get stains on the cloth the same colour as the grout.

Does anyone have any advice?

 

[Tile Marble Granite]

Hi,

We got our bathroom done just over a year ago. The tiler used mapei grout in river grey. I have noticed some of the grout lines turning white and when I try running it off I get stains on the cloth the same colour as the grout.

Does anyone have any advice?

send some pictures