Settings to ensure guest users receive notifications

Occasional Visitor

Hello, we have colleagues at an outside company and have set them up as Guest Users to access shared content via Teams. When we create a post and tag the guest users, sometimes they receive notifications in Outlook but more often they don't, so we've started alerting them via email. Which defeats the purpose of using a Teams post. Their Teams is set to relay notifications every hour, but it's not happening. 
Are there other settings we can pursue to make sure the Guest Users receive their notifications?

1 Reply
Users are in control of their notification settings, including email notifications. There's no "admin override" for that afaik.