No Refund for Cancelled UK Visa Appointment, TLScontact IsUnresponsive

I used Visas-Immigration.service.gov.uk and Tls to make a payment for a super visa for both myself and my boyfriend. Unfortunately, the embassy was closed on the day of our appointment. Since February, we have been requesting a refund of £1800, but we haven't received any response yet, even though the website confirms that we are eligible for a refund. We have not received any personal response from Tls after contacting them through their website, only automatic replies. Despite having visited their visa application center and sent several emails, we have not received any updates or refunds yet. It appears that this is a frequent problem, and I request a clear refund procedure for the two visa payments that were cancelled.