Hey Gyz please Help.

I want to unlock my k800i to all sim cards. After I updated the phone with sony Ericsson Update Service. So when I insert a simcard it says "INSERT CORRECT SIMCARD".

What should I do?

I am pennyless and pretty young. My dad just got me the phone.

If I wont be able to use it He is gonna kill me.

Please Help. Any trick / Tips.

Thanks in advance