please help with my iphone 4s

Hi Folks

I would be so greatful if someone could help me with this issue or at least point me in the right direction.
Im at the end of my tether with my iphone 4s. I bought it a few months ago and it was unlocked using a Gevey sim(imitation). The phone worked for a few weeks and then all of a sudded i could not make or receive calls, i kept getting call failed anytime i tried to make a call. After a bit of research i decided to pay to have the phone unlock through "". I sent them an email beforehand with the imei number just incase the phone was reported lost or stolen. They emailed me back saying that the phone was not reported lost or stolen so i went ahead and paid the 50 euro to get it unlocked. It was initially unlocked to O2 ireland, After unlock it would accept the sim card with no issue but i could not make or receive calls. Everything else on the phone worked perfect. As i could not get the phone working i brought it in to my local vodaphone shop and they were able to tell me that the phone was blacklisted. I then went an bought an original Gevey sim (ultra S) and followed the instructions, I get the message saying phone is unlocked using gevey sim but i am still unable to make or recive calls, i am on ios 6.01 and using baseband 3.0.04.

I would be greatful for anyhelp with this as iv put about 350 euro into this paper weight. Cheers