T-mobile and Sim Card Problem

[cartero]

Hello everyone, recently puchased a jailbroken 3G iphone. Everyone once inawhile my sim card reads "invalid sim" or "sim failure". I have to put the sim in and out a few times before in goes to searching. It finally reads the sim and shows "T-mobile" and I have service. This has happened 4 times in the past week since I got the phone. My question is, should I purchase another sim card? I've had this sim for years. Will it help if I get a new sim? I know its probably not good for the pin contacts in the phone to have the sim card taken in and out often. Just a little worried it's not going to get service eventually. The last time it took along time before it found T-mobile network. Any Suggestions? Thanks

[jake-the-peg]

It's best to get a replacement sim card from t-mobile. It cost about £10.