A lease is a contract--especially a commercial lease, where it's all about what the parties agreed to (in your state, residential tenants have a number of rights which supercede the lease terms). Leases and other contracts are enforced by the courts as per their plain terms. If the lease gives you a renewal right and the landlord is in breach of it, you could potentially sue the landlord for breach of contract, for either monetary compensation ("damages") or for a court order or determination ("injunction" or "declaratory relief") that he must let you renew under the terms of the lease.