Please read! Cant restore purchase!

So I used to have this app on my iPod, and then I bought an iphone, and I already paid for the app, and I wanted my little cousin to play this game since she loves nail salons, but when I tried clicking restore purchase, I couldnt restore my purchase I am really confused please fix this I paid about 2.99 for this and it was kinda expensive!

Ethos444 about Virtual Nail Salon