How to tag a user in Prefect Slack notification?

Is there a way to mention/tag a user or group in Slack when sending a notification from Prefect Automation? I’m using <@U03MK7Z2ULQ> and <!subteam^S037DR39NGP> in the message body, but they just come as plain text. Looks like the message body is sanitized by Prefect. Does anyone have a similar issue or knows how to get it working?