Fraud AC service people

I called https://www.homeapplianceservicecentre.in/ They are such a fraud people. They sent one ac mechanic who didn't see if there is any leakage but told me gas is not there and asked me to pay ₹3.5k as he told our ac is invertor ac. But within one hour no cooling in ac and we found an ac mechanic thru urban cla and they said there are more leakage and also no gas was filled. He showed the meter to use. And told our ac is non invertor ac. When we asked the ac mechanic sent by this company, he said okay I will return 2k. But didn't give money. not attending calls.