job relocation
Are you obligated to uphold a rental lease if you are relocated due to your employment?

Changes to rental lease after move-in
I signed a rental lease for an apartment in FL the original lease was a month to month. I moved in and the apartment they gave us had no phone service. So they gave us another apt in the same building but it was a larger unit, so the agent at the time said the rent would be $100 more and I agreed.I Never signed a new lease. After a few months the complex changed managment companies. I had to move out due to relocation. SO I Went to desk at asked what kind of notice they would need, and the lady replied 30 days and a letter stating why you are leaving.The new managment is now stating we never contacted them before moving out and that we owe them $3400 for breaking the lease. I told them I was month to month and they said the lease does not reflect that.
I ask for them to fax the lease to me and it was completly different and on the last page is the signature we used for the first lease. The lease they faxed me is dated 11/5 and the signature page was signed 9/27 by my wife? This lease also stated our rent was $1050 I was paying $1150. Can I sue them for using signature from an old lease and applying it to a new lease which I never had any knowledge of.