I've taken my I-phone 3g to Mexico but I'm having trouble using it. I checked with Virgin that it would work here and told them when I was traveling. When I arrived I got a text from Telcel welcoming me and telling me the rates for using my phone. I have tried sending texts but they fail to send. When I try and make call I get someone speaking in Spanish and then it hangs up. I haven't been charged for any of this. What am I doing Wrong?