How do I get my money back to my account I make a mistake to purchase high amount of data

Good morning
Mistake was made during transaction intended for data purchase on 07032103362. #12000 was selected instead of #1000 from UBA bank, so this resulted in the purchase of #1000 data
UBA bank customer care was called and they said they couldn't do anything. We should resort to the service provider.
I need reversal of the data to Money
It is money meant for payment of school fees by a single mum. So that the daughter can take her exams hitchfree