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You need to send them a letter disputing the charges and demand they send you a copy of the lease proving the debt. The problem you have is not having the copy of the lease. Without the copy of the lease you might end up having to sue them in court in Texas for breach of contract to prove the fact that your lease was only for 5 months, as this is right now only your word without a copy of the lease. You need to try to contact the manager to get a copy of your old lease. If they cannot produce a lease either, then this is good for you as well because then you can argue they have no copy to prove their claims either. Unfortunately, you will need an attorney in Texas to represent you on this issue, but from what your above statement says you should end up being able to defeat them in court on breach of contract.
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