Boom ...fixed it. JSON view of firewall policy referanced a non existing firewall. Re-created firewall with the same name, and ran set-azfirewallpolicy with same parameters which updated firewall policy and provisioning state now says succeeded. Now to re-delete firewall and piolicy
Firewall Policy .... cannot be deleted since there are Azure Firewalls using this policy

Hi, after using the Azure Free trial to get up to speed with Azure and prepare for Azure Fundamentals and admin exam I have deleted everything after switching to pay as you go. I am unable to delete the last remaining resource which is a firewall policy which does not have anything configured and the the firewall has been deleted. The firewall policy is the only thing listed under all resources but I cannot delete it either from the portal or via PowerShell. I get the same error.
Firewall Policy 'fw-pol' cannot be deleted since there are Azure Firewalls using this policy
There are no firewalls in existance.
Any ideas how I can delete it.