Connection issue w/ T-Mobile

[vandanls]

Since yesterday afternoon my connection w/T-Mobile on my Treo 680 unlocked phone keeps dropping hardcore. It will connect and then drop to nothing, start a "Network Search" and then go to "No Service"... and yes, the bill is paid. I have to restart the phone and then MAYBE it will connect again to T-Mobile for a short while, but then right back to the aforementioned process where it can't find the provider, or ANY provider for that matter (I think it's supposed to roam to whatever available carrier there is if T-Mobile isn't available). The weird thing is that when I turn the phone off and on, even if it doesn't connect w/the provider, it will tell me if I have a new voicemail, even when it's not connected! I don't get that at all. I was able to stop by a T-Mobile store and it worked fine there, but literally 10 minutes after leaving it was back to the same connection problem. T-Mobile said they didn't have outages, but I'm not 100% sure they're not the guilty party, as they nonchalantly make changes to their networks which maybe could effect my connection with this phone.

So my questions is: DID MY PHONE JUST GO BUNK ON ME?

Because service is in and out, is there some adjustment I can make on the phone to improve connection? I've done a hard reset and it did not improve anything. Does anyone else have this same issue? Anyone have a potential solution??