Dropped 3G on the iPhone

It has been 5 days now that my iPhone has been dropping 3G coverage. It is not switching to edge because it still is getting 3G coverage but it is not working. I keep getting time out errors or no internet access.. I then have to swich to edge, sometimes I have had to reboot my iPhone.. It is not just my iPhone someone else here at work is having the same problem.. What is going on AT&T????