Breach and non-performance of a website and mobile app development contract

Hi,

I would like to inquire what are the claims and remedies can I have for the following situation:

1. Delivery date as per the agreement was 110 days, however, it's about 9 months now and the delivery is not done.

2. Website and mobile app developer states that they cannot deliver all the scope that is agreed in the contract (they informed me after 8 months).

3. They threaten to stop the website development if I don't pay the second payment (we pay what they demand although they have not delivered anything yet).

4. The website and app developer promised to deliver the project as per the scope and timeline and advised that I cancel the contract with my previous developer (I cancelled the contract with my previous developer because of this promise).

6. The developer did not allocate dedicated staff for the project although our contract states that they will allocate resources and skilled staff to finish.