We signed an agreement with our tenant with lock-in period of 12 months.Tenant has given us post dated cheques for this period.As per agreement tenant has to pay rent even if he wants to vacate before 12 months. Jusr two months after signing agreement tenant has given 2 months notice to vacate.We have refused and want him to follow agreement but tenant insists and has sent legal notice. What should we ( landlord) do? How to ensure tenant pays rent for lock in period? If tenant wants to return possession in 2 months, should we accept keys?