• Joining client

I was working for a well known firm as as consultant.
I was on yearly basis contract with the company. I served the same client for 2 years and my contract was due for renewal. After the contract got expired and the process of renewal got delayed by my company, I got an offer from client.
As their was no anti poaching clause in my company's agreement and even in my offer letter..
I had put down my papers.
The day i put down my papers, My company asked me not to visit any client.
Now here i am doing nothing for months.. serving my notice period sitting at home, and not getting paid for the same because i have an offer from client.
My company has put an allegation of breach of integrity and breach of trust on me. It has also refered me as a criminal in phone conversation.
And now it wants me to to sign non solicitation letter, after my resignation.
And they are threatening me by saying that it would be a legal matter now. and they will be sending court notices to me.
Please help me with the same.