Worst Service Provider

I did a voucher to a wrong number and i called Tymeback to reverse the voucher if it's not redeemed, they checked, and the money was not redeemed. The lady told me that they can reverse the transaction i have to wait for 7 day, if the person doesn't redeem the voucher, it will be refunded. I told them that it's the wrong number, but they refused to help. They are the worst service provider. How do i trust them with my money if they are like this?