Iphone 3gs 5.0.1 - 5.0 baseband lost ?

[llGIBBAll]

Hello please can anyone answer this,
I bought an ipone from america on christmas, it came with the version 4.1 with baseband alredy unlocked so i could put my sim card in it. Anyways the other week i decided to update this iphone but now its not letting me insert my sim card it wont read it, ive tried looking on the internet i cant find nothing any suggestions please people

 

[iAppleseed]

Hello please can anyone answer this,
I bought an ipone from america on christmas, it came with the version 4.1 with baseband alredy unlocked so i could put my sim card in it. Anyways the other week i decided to update this iphone but now its not letting me insert my sim card it wont read it, ive tried looking on the internet i cant find nothing any suggestions please people

Jailbreak it, install ultrasn0w fixer for 5.1 first, then ultrasn0w.