You'll see a red banner in the Dashboard that says: "You have an integration that needs to be reauthorized. Click here to correct this problem."

Click the link in the error message, or go to the Locations and Integrations page (in Settings) you'll see a red dot next to the integration status that says Reauthorize: 

This means Thrive is not receiving any data from that integration and is not able to send any inventory data. Effectively, the integration is disconnected from Thrive.

Easy. Click on the integration and use the gear wheel in the integration settings to reauthorize. 

(NOTE: You will need to be the Account Owner for Thrive in order to Reauthorize an integration)

That will prompt you to reconnect the integration. You'll need to have your point-of-sale login credentials handy.

This is a designation from your provider. It means Thrive's access has been revoked from their end.

Thrive has no control over this. We also have no access to see exactly what changed that caused the permissions to be revoked. All we know is that the point of sale provider told us we no longer have access to the information.