The screens will explain
Edit: forgot to say that the screens are in french
I don’t recognize your device, may I ask how long ago it was released?
“Cette application n’est plus compatible avec votre appareil” suggests that the phone is pretty old.
Edit with more information: between 5.3.5 and 5.4, the devs changed which version of Unity they used. I could see this change making some devices obsolete.
I bought it 1.5 year ago, idk when it was released. I already struggled to get 5.3.5 version (as much as to get the play store screen because gems of war doesn’t appear in my play store)
Did you try the version that is on the Amazon App Store?
Looks like Miui phones are not compatible with Google Play Store. Appareils compatibles - Aide Google Play
There are several instructions online on how to install apps on phones like this. Most of them are how to install Google Play which you did… Maybe this one instead will help? https://www.reddit.com/r/xiaomi/comments/4cuk0h/_/
I actually have an xapk file of latest version but it says that it doesn’t match my current version. If i uninstall gow, can i get my account back after?
You need to link your account first, then yes you can uninstall and reinstall. https://gemsofwar.zendesk.com/hc/en-us/articles/202984335-Recover-or-link-your-lost-game-account-in-Gems-of-War This article also links to how to register your account.