I just purchased a P7040 go phone. My previous AT&T SIM (Cingular) is not recognized. The chip layout is different. What phone number can I call to talk to a person? When asked for my phone number, I get transferred to the GO phone line and no people are available.
You can, in fact, reach a customer service representative by dialing 611. When prompted by the automated voice response "lady", select "Main Menu" and then say "More Options". Keep repeating "customer service" over and over again and the system will eventually give up and transfer you to a live-chat CSR that can assist you with your SIM issue.
Another alternative would be to call 1-800-331-0500 from a landline phone. That is AT&T's customer support phone number.