Use the PUT method to modify, or update, your existing Views and Alerts.
You will need to include both the View's name and viewid in your request, so that the appropriate View is updated.

NOTE: Be aware that the PUT action will replace the existing view contents with your request body. This includes View-specific Alerts and/or any filters. Properties not specified in your PUT request will be removed.

Click Try It! to start a request and see the response here!