Apple Iphone noob, cydia app wont run, tmobile access denied

[DigitalDeviant]

Hi there I did some google searches and am still not sure what could be wrong with this Iphone i've acquired.
It used to run smoothly on the t mobile network but now there is no service and wi fi does not work either.
On top of this the Cydia app and most other apps wont run. The current fw version is 5.0.1.
If someone could direct me to the possible problem it would help me zone in on the solution. Much thanks in advance!

 

[BORTZ]

I dont know for certain but i know if you are on a GSM phone you can mess up your baseband. You have to jailbreak in a way that doesn't interfere with your baseband.

 

[Fizzlicous]

You have encountered some sort of glitch in the iOS software, if you haven't solved this already try restoring. If you have unlocked do what you need to preserve your baseband