Xiaomi India — Its been 45 days i still didn't get my mi4i from the service centre

Address:	Kolkata, West Bengal, 700039
Website:	www.mi.com/in/service

I submitted my mi4i on 14th of july due to issues of microphone not working and phone was switching off automatically several times a day. I was assured 20 days delivery from kolkata mi service centre. Kasba branch. Regardless of which my phone is still out with them. They are saying that they have ordered for the parts from bangalore but those parts are not dispatched. It's been 45 days what the hell is going on with this useless company. I am gonna file a case against this.