Problem downloading app while living in a different country

I am currently living in South Korea and originally from UK. I am trying to download this app, pass by KT or SKT which is supposed to help verify you as a person. But for some reason I cannot download it. I am be able to download app the whole 2 months I have been here but I cannot with this app. I have changed my region/country in the App Store and in my settings as you can see down below the App Store is in Korean. But once I try to download something it comes up with the message below about my account not being valid for the Korean store so it goes back to the UK one which the I am still unable to download the app from and it says The app is currently not available in my country or region. Currently it is an endless cycle is there anyone out there who knows how to fix this issue