Apple has lock out my phone;

Im a current customer in good standing with ( AT&T/ APPLE) and about May or June of 2009. My Iphone stop working. I did not download any applications nor software that Apple did not advertise on thier web site. Now I can not make any callfor my phone. I cna not afford to buy a new apple phone at it's current $600.00 price, and why should I ? Im a current cusstomer in good standing. Well now I can not use my phone. Can you help me ?

Steven Victorian
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