New tile grout on kitchen floor got dirt/sawdust on

[gobblygook]

We've had some beautiful tiles laid, then a whole manner of additional stuff done to a kitchen. The smokey grey grout between the tiles looks like it's become dirty - white, brown, flecks of stuff.

Can't tell why it's become so bad. We scrubbed it down yesterday (moving in this weekend).

Any tips for how to get it back to looking good?

Ta

Mines is the same , interested to see what people advise x

you can take a piece of steel wool and water and gently remove the top layer or you could buy a SPECIFIC scrapper to do same or you could buy a grout pen and re colour , sounds like something is (obviously)sticky?as it should have been brushable to clean, was enough time given for them to dry ? my builder brothers always at least double the" recommended on container drying time," as that is an ideal condition situation, hope this helps