Liquid Capital
Policy cancelled but account still debited

I cancelled my policy because my car was a write off. I received a confirmation email and an agent called to confirm as such on the 17th of December. He said the refund of premiums takes 21 days.
On 28th of December my account was debited again. When I contacted the call centre today and spoke to Nosi. She said there was no record of cancellation, and that the finance department is all on leave until the 13th of January. She then proceeded to cancel my policy afresh
I need my debit order reversed and a refund of my premiums. I need written confirmation that the policy is in fact cancelled