Apple India — fraud in apple iphone service

Address: Surat, Gujarat, 395010

Website: ivenus.in

There was some problem in receiver speaker in my apple iphone 6 plus as volume was coming too low, so i visited venus data products (Apple service center) on ghod dod surat (Gujarat) on 19th august 2017 in surat.
After initial checking they told me that there is some hardware problem in receiver speaker & will have to be replaced, which will cost about rs 3200.
As there was no alternative option i agreed to replace it and handover mobile to them.
They return the mobile after servicing and i checked it, it was working fine so i paid them rs 3200 as asked by them.
On asking for invoice/bill for the same, they made photocopy of the estimate and gave me which neither had part change description nor any cash receipt or service report. The estimate too did not have anything mentioned about any part change or money receipt.
On insisting for proper bill the executive asked to talk with the center manager.
It took me by surprise that he too denied to give a proper bill and said consider this photocopy only as the bill for which i did not agreed.
After further conversation when i did not agreed he said bill is generated from head office and not from this center so i cannot provide you with bill for this and said visit after two days for bill just for getting rid of me.

In my opinion its a clear case of fraud, they did not changed any part but just cleaned the dust over from the receiver speaker and that's why just took payment from me without providing receipt from me.
I did not expected such a thing from a reputed company like apple and never ever heard anything like this in my life before that company cannot provide invoice/bill/money receipt.
They clearly received this rs 3200 from me as black money and have not intention to show this which probably will go into the pocket of service executive and manager

I want a proper answer for this from the company and refund me my amount along with compensation.