Date: __/__/____ (Date)
Subject: Complaint for car service __________ (bill invoice number)
This is with reference to the car service provided by your service center ________ (car service center name) on __/__/____ (Date). I am unsatisfied with the car service done.
Firstly, the car service ____________ (delayed/not done properly/really inadequate/ over-priced/any other issue)
Secondly, _____________ (mention all points related to the service)
I want you to either ________ (mention your point and the resolution required). I have enclosed the bill related to the car service for your reference.
I look forward to your reply.
__________ (Your Name)
__________ (Contact Details)