Need to know how to unclock Samsung V206 from AT&T in USA.

Anyone know please tell me how to unclock that phones somehow either using unlock code by generated softwares or anykind of device that help me to unclock that phone. Thank you very much to all your helps.

I try to input the following code to unclock it but the last code It said wrong code. If anyone figures out that let me know. Thank you very much.... the codes I got are:

*2767*MEDIA#
*2767*FULL#
*2767*CUST#
*2767*WAP#
*2767*STACKRESET#