Check your spam and junk folders, as well as any tabs in your inbox, in case emails from Slack are ending up there.
If not, ask your IT team or email service provider whether the emails may be being caught by your email system. They might like to check that emails from firstname.lastname@example.org and email@example.com aren’t blocked.
Missing team invitation
If you haven't received your invitation to a Slack team, check with the person who invited you that it was sent to the correct email.
Team Owners and Admins can check pending invitations to make sure that email addresses are correct at my.slack.com/admin/invites. To send a new invite to the correct email address, just click the Invite New Members button.
Didn't receive a weekly update email
Weekly team update emails are sent only if your team has four or more active users and has sent 100+ messages in the last week. These emails are sent only to Team Owners and Administrators.
Not receiving DM and @mention notifications
To avoid filling your inbox while you're away from Slack, email notifications of direct messages and mentions are bundled and sent every 15 minutes.
Note: Email notifications won’t go out if Slack is active on on your desktop or mobile.