Refund requested but still no response from Capitec

So I cancelled a policy with capitec on the 11th of December and on the 15th the cancelled policy Debi check went through. I received a email on the 21st saying the policy was cancelled. Upon trying to contact the bank they said there is nothing they can do to help. I spoke to a agent and he/she informed that I am eligible to request a refund. I have been mailing them back and forth and no response. This is not the first time it's happening. They will reply after a couple of days to inform me that the incident had been closed and there is nothing they can do... I really need assistance in this regard.