If the Azure function is deleted and reinstalled the “Call URL” for the function needs to be updated in the ManagementConsole. The “Call URL” can be found in the output of the installation script, or from the portal.azure.com.
The “Call URL” is in the agent details screen in the Management Console, and can be updated by clicking the “Update Called URL” button (circled in red below).
The actual URL to put in the Management Console can be found in portal.azure.com. Login, Click on Function App, Click on the “techidmgrXYZfa” (XYZ will be some number), Click on Overview, Click on “Run”, click on “Get Function URL”, select “default (function key)”, Copy that URL and put it in the Management Console.