Double Billed - What do I do?

My last payment was overdue by 3 days, so I manually paid the balance (on Thursday 3rd) via their automated phone service because trying to pay through the app didn't work (after the clicksafe from my bank finished it just said "Sorry something went wrong and this isn't available").

The online chat is greyed out and I now have two iD mobile payments on my statement (one on the pending transactions tab).

Could the app have glitched and taken the payment even though it said it hadn't?

I'm really worried because I'm on low income sick benefit and I have other direct debits due and I really can't afford to go into an unplanned overdraft with massive charges because of this.

Pending transaction: (this will go through properly on Monday)

And then this one taken 1 day after my attempted payment via the app and the successful payment using the phone service.

I know it's not a lot of money to some but they've effectively taken the money I was going to use to buy food this week and now I'm stuck and don't know what to do.