Language settings per user
1. Verify you have properly setup the language you want to assign to your user by checking the Localization guide.
Choosing the user interface language
2. To change the user's interface language, you need to login with the user which you want to modify the language.
If you are a SiteAdmin user, you can use the impersonation feature to login as such a user directly from SiteAdmin.
3. Once in the application, go to Settings > Settings > Localization
Note the languages available will depend on the privileges granted in step 2.2
4. Save the changes, then refresh the browser to see your changes applied.