I have minutes but it tells me insufficient balance – Voicy Phone - Prank Dial Call with Voice Changer Review

I loved this app until I bought 20 dollars worth of minutes thinking the order didn't go through but it did and it does not work I have taken screenshots where it says insufficient balance and contacted the maker numerous times through the app and I have not got a response, if they are not going to fix it or if it can't be fixed I want my money back!
Review by Kevin Godwin on Voicy Phone - Prank Dial Call with Voice Changer.