Absa prepaid electricity mistake

On the evening of 22 September I bought R200 prepaid electricity using the Absa banking app. The app immediately said payment unsuccessful, so I didn’t think the money would be deducted. After trying again (another R200), I got the same response. I realized R400 has been deducted from my account, without getting an electricity number. Because the Absa app said it was unsuccessful, I figured the sms I got about money being deducted was a mistake. So the next morning of the 23rd of September I bought another R200, at which the payment was unsuccessful again. After all I lost R600 to Absa’s app’s mistake. This morning (25th of September) I went to Absa to explain my problem. They didn’t do much and only gave me a reference number. They can give me the R600 in electricity, but I’m moving in a few weeks, which means the electricity will be a waste. This was completely Absa’s fault. Please help.