Disappointing customer service

My debit order was taken off twice on the 20th December as well as me making a payment on the 19th for a missed debit order. I inquired with them that the debit order was doubled and they need to reimburse me. I queried from the 21st of December. I sent them screenshots as well as my bank statement, showing them the 3 payments. Each email comes back with them saying I must wait 7 days for the DO to clear and then I can query it. I did that then I get and email to provide them with my bank statement again. I told them to refer to an email sent AFTER the 7 days cos I can't keep downloading statements all the time. For the past 2 days I've just been ignored with automatic replies. Tell me whats so difficult to go into my account and see the overpayment and reimburse me. It's not a little money. I have a kid to feed. Who can just let that amount of money slide at this time of the month. There's just no indication of a resolution.