A: The only instance in which a landlord may cancel a lease agreement is if the tenant is in material breach of the contract despite being given 20 days written notice to remedy a breach. If the matter is rectified by the tenant within the 20-day notice period they are entitled to continue with the lease. The 20-day notice period is a provision of the Consumer Protection Act (prior to this legislation tenants could be required to remedy a breach within 7 days).