Double payment

I missed my payment as my paydate fell on a Saturday fine, I received a link to pay online then on the same day it debited again. I called on Tuesday and was referred to a Watsapp line as both payments have not reflected yet. I sent a Watsapp and only the next Friday then both payments reflected and I requested a refund on the Watsapp line and the response was simply “refund requested” I called the call centre and they asked for all the proof of payments again which I did send and they advised that that turn around time was 7 days, however it’s been more than 14 days and when I follow up on the watsapp the response is just “refund request escalated”. It’s almost time for another debit order and I’m afraid that they will double debit and give me the same excuse ms again.