Pathetic service

Where do i start. Pathetic service. Last debit order was end april 2024. Received my paid up letters but no clearance certificate. Mind you they still owe me a refund. After numerous emails still waiting on refund and clearance certificate. I keep on asking for a manager to call me but nothing. They keep on saying the matter was escalated to a TL. How can they not resolve my query, pay my refund and send my clearance certificate. Pathetic service is an under statement