need help....3g n network drops

man..looks like i brick my phone
one day i was jjust messing with internal setting with master code n all
and i think i changed my network setting or something
sometimes my network bar drops to one bar or 0
and when it happens...3G drops with it n i cant make or recieve calls nor texts
and it says emergency calls only when i try to call
but network comes back up but not 3G
sometimes restarting fix it but other times it doesnt..
i have to restart it couple of times
i just want to know if you can tell me what the problem is before i take to at&t
i have insuarnce so i lost my phone...lol

Unless you dropped it in water  . jk

I bet the problem came from you messing with Internals. .

If you have to resort to flashing your phone...

nevrmnd
did little research and found the firmware
flashed my phone and looks like working fine
for now
Thank you guys and girls.

Try this dial *#63895# this will take you direct to your network mode automatic should be checked for 3g to work the one below it says gsm only thats the edge network if checked you will only get the edge network. there are a bunch of other choices but I am advising you not to play around with them if you do dont blame me if you brick your phone. but this will at least let you know if you are in the correct network mode.