This is to
draw your attention to [state the nature of your complaint]. I would appreciate it highly
if you take appropriate action towards resolving my problem [state what you want done
about your complaint].
hereby attaching copies of various documents [List the invoices, bills, letters, notices,
contracts and receipts, etc.] to support my complaint. Kindly contact me using the
information shown above, and I expect your reply by [date]. Thank you for your assistance.