Cannot restore purchases

I installed this on an older iPhone with an older iOS and it asked if I wanted to install the last compatible version, so I did. Once installed I tried to restore purchases and for an unknown reason it would only default me to the US iTunes store and I could not restore purchases because I obviously bought it from the Japan iTunes store. I only have an account with the Japan iTunes store so I am unable to download what I have paid for. I am sure I cannot get a refund and I really dont expect anything will be done about this, so I am just giving a warning to others not to buy any of the in-app content because you could likely get ripped off just as I have been.

nonicknameavailablesoijustchosethis about Baby Shark Best Kids Songs, v3.6