How Do I Handle My Landlord That Is Trying To Charge Me More Money For Leaving Early Out Of A Lease?

My husband and I are being relocated because of his career. We gave our landlord 30 day notice that we will be vacating our home. When we first re-signed the lease agreement for the second year, one of the management representatives for the landlord told us we only have to pay 1 month rent to break the lease. However, now they are charging us 3 months worth of rent, even though we will be paying our final month (even though we'll only be in the house for 12 days). None of this is included in our lease agreement.