Confidentiality and non competition agreement

Hi Respected Lawyers (Sir) When I joined a company, I have signed the above agreement . Later company hr called me and asked to resign because client don’t want to continue the contract. They told to email my resignation. Having said that I have resigned . Done all formalities . During covid it was tuff to get another job. So I tried to contact client for any work if pending or any related work if they can offer. The client company located in America they took my request and gave me job offer to join. After 3 months, the previous company is threatening me not to join client company due to the above clause . They are planning to send legal notice in India. Currently I am in America . I don’t no what to do and how to counter them. Very disappointed. I have faith in Indian judiciary. Please suggest me . Note: current company is not a client anymore to my previous company. So how can company file law suite against me for joining client company? I am middle class person and with lot of hard work I have reached to this stage . I wish everyone please be safe and get vaccinated . Thanks .