Can we sue company who hired our company?

We are too familiar with companies just pulling our contract, updated contract to read as follows: In Our Contract it Sates. the following Cancellation Of Contract Policy: This contract may be cancelled If MFR is found in breach of this contract client must submit the following for breach of contract Notify MFR in writing within (30) Thirty days of breach of contract.MFR shall have (30) thirty days from notice of breach to resolve or fix these issues.If after 30 days from written notice, problem has not be resolved Client may cancel this contract with proper written notice to and reserve the right to dispute this breech Customer understands that any delay on payments to be made to MFR may result in appropriate legal action. They sent letter Friday canceling but also with September 30 2018 not 2017, huge good on their part. Loosing two year contract, no one contacted us with recent issues.