Sony India — bluetooth device

I had given my bluetooth device to sony service center on 10.12.2017 vide their job registration No.J73609824 dt, 10.12.2017 for complaint "No Sound" . I visited their service center several times. At last they have informed me two weeks ago that the device in not repairable and they will give me other device. yesterday I again visited their service center but they have not given me any device nor they have given me my repaired device. Their at Service center On phone some sh. Prashant Kumar, Service Head talked to me and said You had to talked to me before come to here. I have no device to give you. When I asked him that more than 07 months have passed but nothing has been done and I will go to consumer forum. In response to this he begun shouting on me and said "go and whatever you want to do do". He misbehaved with me instead of solving my problem. This the company like Sony is dealing with their customers. My this complaint must be treated as last notice to Sony and after that I will take legal action against the company for mental harassment and financial burden.