Breaching contract by the service provider and possible action

Compensation for poor performance & false accusations.

We hired a consultancy agency to provide us with their services. During our working relationship, the deliveries were consistently late, and the service was unreliable.

We gave them numerous chances to improve performance and meet timelines.

The details of these problems have been communicated to them repeatedly but they did not address the problems in a timely manner, causing us extra expenses in addition to mental and emotional agony.

During the project, my father passed away & they have used this matter as an excuse to pause work on the project without notifying us causing us further delays.

Recently, we serviced them a notice for contract termination for their failure to adhere to mentioned services.

In response, they have wrongfully accused me of talking badly about their staff & making insulting & inappropriate comments about their work which have made the working relationship difficult.

Do we have legal rights to pursue?