Bad service

I am writing to formally escalate my refund request. I made payment for installation on 3 March. No installation was ever completed. As a result, I requested a refund on 17 March and was informed that the refund process would take 30 working days. It is now June, well beyond the timeframe provided, and I have still not received my refund. Despite numerous calls and emails, I have not received any meaningful assistance or a clear update on the status of my refund. I request immediate confirmation of the status of my refund and a specific date on which the funds will be returned to my account.