Contracted this company in 2012 to replace my roof...

Contracted this company in 2012 to replace my roof. Everything was fine until last year, some shingles had come off our roof so my husband contacted this company through email and received no response. There was a huge rainstorm and the roof started leaking in our back bedroom. Since we received no response from this company and we were afraid we would have another rainstorm we contacted someone else to replace the shingles on the backside of our roof. No problems until two days ago during a rainstorm, rain started leaking in our front bedroom. We contacted the company and did receive a response. The representative comes out and says since someone fixed the backside of our roof, the contract we had was null and void. We told him my husband had sent an email, he said in other words they don t respond to emails we should of called. The contract we were given states the labor is good for 10 years and the material is good for 25 years; it does not state if another entity fixes the roof the contract is voided. The contract is signed by my husband and their company representative . The representative goes back to his truck downloads a totally different contract which has the stipulation if another entity handles the roof the contract is voided, keep in mind the contract he downloaded has no signatures. I just want this company to stand behind the original contract and replace the shingles on the front of our roof. I m waiting to hear from the president of the company, if I don t I will be reporting them to the Better Business Bureau and taking them to small claims court.