Refund of over payment

When I renewed recently, apple took 3 full payments out of my account, I effectively paid triple for my premium subscription. I sent a refund request to apple and they refunded 1 of the payments but also cancelled my premium subscription, so I have now paid double for a subscription that I can no longer access.
apple are not responding to any further request from me, so I’m looking for advice on how to get access to my premium subscription and a refund of the extra payment.
Thanks

Answers