Home services Bangalore - Fraud Service center

My * years old Samsung Microwave had some issue, so i searched Samsung service center number in Google. I found one number they claimed themselves as Authorized service center. ( I was in hurry so didn't get verify their authenticity). I called to ***********, one lady asked me is it under warranty or not,i said no.She raised a service request and said technician will visit your house shortly. After * hours technician(Imran) came to my house and did some basic check.Then he said sir i need to take this to our Service center. I said Ok n went out of city for * days. After * days i got a call from technician (Sam) and said need to replace Magnetron n motor which ll cost you around ****+*** = ****. I said fine and he came back with microwave. My wife checked and it was working fine. We paid him **** (****+ bulb cost *** + service charge ***). But same day evening it stopped working again. After i tried to reach them but nobody was answering my call. Next day as well nobody answered our call then i call to Samsung CC and told them all story.I know it was my mistake but it already happened. Now they arranged a service engineer from Samsung. He visited our house same day and checked the microwave. To my surprise except bulb none of the part is replaced. Even they didn't break the warranty seal.and on magnetron old is still mentioned.I have attached the pic of Magnetron. There was just a loose connection , so he fixed that then and there. After i text them couple of times , request them kindly refund only **** which you have taken without changing anything but nobody care.They know normally people don't file a case or go to Police for such thing. I am hoping i ll get some help from this app. I am not able to attach multiple file. Please let me know how can i send more evidence to you.