How to change language in Apps

when I change the language(localization) in my app, the previous language will be displayed in the chat page, how do i sync the chat language after changing the language in my app?

by the way, Changing the language in the app does not terminate the app. (just change the language bundle path).

following is the Chat UI building func :

    UIViewController* viewController = [ZDKMessaging.instance buildUIWithEngines:engines configs:@[messagingConfiguration, chatConfiguration] error:&error];

Thanks.