I have a recently installed Ceramic tile floor in my kitchen. There are a couple of areas where the grout has ccome out. I tried scraping all the loose particles out and putting new grout in a few times but in a few days it just happens again Is there anything i need to do or apply anything before I try again? My wife is driving me crazy about this. It is in a fairly high volume area. Alsa, how long dhould I let it dry before letting anyone walk on it again? Any suggestions would be greatly appreciated. Thanks Bronco1995@hotmail.com