For when the first complaint got you a voucher and a shrug

You complained, they offered a voucher that does not cover your loss, and that is where it stalled. Give it the company, the original issue, what they offered and your actual loss, and this writes a firm escalation to their complaints director. It references your original complaint, says why the response is inadequate, cites the relevant law and sets a 14-day deadline.

I already complained to [company] about [issue] on [first complaint date]. They replied with [what they offered], which doesn't cover my actual loss of [amount or impact]. Write a firm escalation letter addressed to their complaints director. Reference my original complaint reference [ref number if known], state why their response is inadequate, cite relevant consumer law, and give a 14-day deadline before I refer to [relevant ombudsman or small claims].