Intellipaat — Not paid for my contract as trainer

I have 12 years of IT industry experience, intellipaat contracted me as a trainer, I have given 32 hours of training and immediately after this, they canceled my contract without payment.

I didn't attend my calls nor answered my emails. They did approached me after seen my profile in LinkedIn and given me contarct after doing sample class.

After 3 months they are saying student feedback was not good. And refuse to pay, how should I proceed.

They changed 3 trainers before me, worst management, non professional behavior.

They are giving false promise to students and blaming trainers for their dissatisfaction.
They promise in 3 hours they will teach entire technology, in reality it will take months.