When someone asks to stop getting a learning journey's emails — often because they've left the company — the way to stop them is to remove the person, since Knowly doesn't have a separate "turn off emails" switch for a participant. The only question is how far to remove them: from one learning journey, or from your organization entirely.
Start by clarifying what they want
Removing someone stops their emails, but it also takes away their access and their place in the journey. So before you act, check what they're actually asking for:
which learning journey the emails are coming from
which email address is getting them
whether they should leave just that journey, or stop hearing from you altogether
If they only want fewer emails but still need to take part, there's no email-only setting — so don't remove them without confirming that leaving the journey is really what they want.
If they've left the company
If the person has left — a former employee, someone who's retired, or anyone who should no longer have access at all — remove them from your organization. That takes them out of every learning journey at once and stops all Knowly emails to them. See Removing a participant from your organisation.
If your organization syncs users from a directory (SCIM), remove them there first, or the directory may add them back.
If they should leave just one journey
If they should stay in your organization but come off one specific learning journey, remove them from that journey instead. Their account and any other journeys stay as they are. See Removing a participant from a learning journey.