Refund issue

I incorrectly transferred funds into a cancelled policy I had with Old mutual thinking I was funding my Money account with them. I raised this with them and a refund case was submitted, I submitted my ID, proof of payment and refund form, a week passed by and there was no correspondence from them, the following week I did a follow up and was told that it will be escalated because there is no update. This morning I received an email stating they cannot issue the refund because they are not picking up if there was any money paid to the policy to begin with. The payment was done on the 02/07/2023. How is it possible that is is not reflecting? I am writing this because I called into their call center and I'm still told that there is no money reflecting and once again they will escalate it. I know the process, nothing will be escalated, they just want me to give up. I don't care if it's a small value, I want the money back.