Unlocking of 'sim free' iphone 4s
I'm wondering if anyone has any bright ideas,
about 6 months ago i decided i needed a new phone however still had 6 months left on my contract before i could cancel or upgrade. so i went to the carphone warehouse and paid nearly £500 for an iphone 4S which was apparently sim free, i was advised that although the phone would lock to the first sim card i put in there but it would be easily unlocked if i restored the phone in itunes. So i've waited until my contract is up, plugged the phone in and low and behold i can't unlock the **** thing. I have been to apple who told me to go to t-mobile, who told me to go to carphone warehouse where i purchased the phone, who told me to go back to apple. I'm now feeling rather peed off that i have spent £500 on a phone ive only had 6 months of use out of.
has anyone rectified this problem? I dont particuarly want to go to another source to unlock the phone as often they jailbreak them and this will void the warranty of the phone. just looking for an answer of how i can get the **** phone to be unlocked so i can use another network provider.
UK suggestions only please! thanks!
iPhone 4S, iOS 5.0.1