Send confirmation email in correct language with Apple connector

Question is, how we can send the confirmation email template in correct language, when user registers via apple connector.

When the user gets redirected to the form, there are two options how the user can register.

  1. by providing email and password
  2. via the apple login connector

When the user registers via his email, the language will be saved in the user object, we have a pre-register action which saves the browser language and then we send the correct template via conditions in the email template.

When the user registers via the apple connector, no language will be saved so we send the default language template.

How we can add the language to the user object when the users registers via the apple connector in order to send the template in correct language?