There are various ways to notify a user. You could have a separate app that reads from a common tulip table, when status changes or message is saved it will display on the screen of this other app.
You can send an email from the app (only to registered users) and SMS (if phone is entered and verified)
You can send an SNS / email AWS SNS Messaging layer for Tulip Apps
Or SMS Sending an SMS to any phone number from tulip – Michael Ellerbeck
Or Teams connector M365 Teams Connector
Or Teams Teams integration with AWS lambda + Postgres & Tulip – Michael Ellerbeck