Azure data can be removed by deleting any Enrollment or Service Principal. You can also retain historical data and instead stop the flow of new data by retaining the Enrollment or Service Principal but invalidating the shared secret used to connect Azure to CloudHealth.
After deleting any Azure infrastructure, it takes an overnight processing cycle for the data to become no longer visible in CloudHealth. If you wish to instead retain the historical data across Cost & Usage and Assets please instead follow these steps: