Why is my subject sd.admin.outgoing.email.default.subject?

[Dawson Toth]

All emails going out from my service desk have the subject, "sd.admin.outgoing.email.default.subject". I've configured customer-notifications/template as "Housters: ${issue.summary} ${issue.key}", yet it doesn't appear to be used. Has anyone else seen this issue? I've spent a couple hours poking around everywhere I can think of in the settings, and haven't made any progress.

[Denis Legostaev]

same issue, but only for one user in our Jira, the rest gets email subject correct

[Thomas Van Buggenhout]

I have the same issue as Denis, only 1 user is impacted.
Have you found a solution already?