Display Language on Android App

I currently use the Android App, available from the Play Store, duly updated. My native language is PT-BR. The language is properly configured on my phone, however the application is presented in the standard English language. I appreciate any guidance.

PS: Wouldn’t it be reasonable for the language setting to appear in the application menu?

Could someone help by guiding me to change the application language?

I found a bug when language has country code, eg. pt_BR or zh_TW. Take a look: