My City Networks Committed to a 6 mon. contract & held me liable for a 12 mon. contract. Second time done to us. Miami Florida

I made it very clear that I wanted to only sign a 6 month contract. I was verbally told in person, at my office, that this would be no problem and would be handeled by the supervisor (Nicholas Christo) at their location. I signed a year contract, with the promise that the contract would be altered to my 6 month requirement. At the end of the 6 months, the office has called me, telling me I have a 12 month contract, and I discussed with them that it was 6 months, as per our conversation upon signing. Now they have a collection agency threatening to damage my credit if I do not comply and make a payment for the rest of the 6 months.