In Email Builder, you’ll need to add the footer text within the message content, or you can setup & add the footer content via Email Builder (Omail) > Tools > Opt-out Settings
It can be setup at the organization/database level or deployment type level.
Select Opt-out footer (HTML) and add the footer text within the Opt-out Link Asset box. Save.
HTML footer verbiage must be coded in HTML. We cannot store Unicode characters, only ASCII text is permitted.