Grout over newly grouted floor tiles

We've had a hard two days finishing bathroom, the flexible grout we used took a long time to go off!
Dont know if it was something to do with the edges of the tiles being highly polished?? They didnt look pourous at all.

It was touch and go with the amount of grout we had, and we finished the floor but we were not 100% happy!

So when we turn up 2moro were expecting the worst!


Q- Can you grout over areas that are suspect or will we have to rake areas out and re-grout......bearing in mind we've only just grouted today and we're back in morning icon_question.gif

Read more: //www.diynot.com/diy/threads/grout-over-1day-old-grout.421579/#3280105#ixzz3NRXxZq3b
**POSTED THIS ON HERE, AS NO LUCK ON TILING FORUM**

UPDATE
Grout has sunk a little as expected, due to not going off quickly, so its created a dip in the grout lines.

Factors for a ****e grout job are-
Mix grout too thin
Dont use enougth
Let it take a couple!!!!!!! hrs.......hrs... to go off!
Sponge it down before its ready
The above should get you a **** grout finish you've worked your ars of for