Can't install country-restricted app even if I'm physically in this country I am trying to install this banking app from Google Play: https://play.google.com/store/apps/details?id=pl.ing.ingmobile

This app is allowed to be installed only by users in Poland. My Google account was created in Brazil, but I am in Poland since almost 7 months, so I should be allowed to install this app.

On Google Play, it says: This app is incompatible with all of your devices., further more, on my phone's tooltip, it reads: This item cannot be installed on your device's country..

That is very problematic, as this device was bought in Poland, is using a Polish SIM card and most importantly, it is physically in Poland, so how can it not be compatible?

How can I force-install this app on my device? It is a Sony Xperia Z Ultra, rooted and flashed with CM12.1.
Add a Polish credit or debit card to your Google Wallet account and remove any other cards.