Server switcher not working on android app

Server switcher not working on android app

I am testing Zoho Writer and Sheet to using them for my businesses.
I have both an account on Europe server and China.
The server switcher icon on Android app, in the right upper corner of sign in page doesn't work. It keeps directing to the European server, clicking on the CN icon doesn't change its status to COM

Problem is both on cellphone and tablet, both under Harmony OS