Doccle sends you mails in the language set in your Doccle account.
To change this language, you must change the language setting in your account.
Remark: The language setting of your account influences the language of the texts / buttons in your Doccle account and the emails you receive from Doccle. The language of the content of your documents is determined by their sender (but can sometimes be influenced by the language of your account).