Last year my wife purchased a cellular phone from a Movistar dealer in Colombia and signed up for prepaid service. Everything worked great at first.She left Colombia on April 25, 2007 and took her phone with her. She returned to Colombia on Nov 4, and purchased a card to add funds to the prepaid phone.
She was not allowed to add funds to the card. She went to a MoviStar office in Barranquilla and was told that the problem was she had converted to a contract wiht a monthly billing on Aug 20, 2007 and never paid the bill.
Therefore, she is unable to add funds to the prepaid phone, or otherwise place any calls from it. MoviStar claims that she was called on Aug 20 and agreed to the monthly billing. Not a likely event since the phone was not in their service area and she never spoke to them (and she is only visits Colombia occassionally, would have no interest in such a plan).
I called MoviStar in Spain at: +34 680013300 and was told to try to Colombia office at: +57 1-650-0000 (and another number in Spain that seemed to be a very confused customer). At their office in Bogota I was told a different story.
I was told that after you don't use your phone for 3 months, you lose the number. That's fine, except the number that worked on April 25, still works for receiving calls. I was told that they would check into it and call my wife.
She's still waiting and still can make any calls.
Maybe MoviStar would like to make a response here.