I have Norton VPN turned on permanently on my laptop and my home office computers. Screenshot is attached.

Do you have this issue when not using the vpn service?

No, it's only when the VPN is on and only in Firefox.

If it's a VPN issue why is it only happening in Firefox but not in Chrome or Edge?

"You don't have permission to access..." errors are characteristic of a firewall that protects the server against misuse and this firewall thinks something is suspicious about the HTTP request. If you use a proxy or VPN then try to use a direct connection. You can try to clear the Cache and remove the Cookies for websites that cause problems via the padlock button or via "3-bar" Firefox menu button (Options/Preferences) to see if that fixes it. I've also seen cases where having "Resist Fingerprinting" enabled caused this issue to occur.

• https://support.mozilla.org/en-US/kb/firefox-protection-against-fingerprinting

If this all doesn't work then you can try "Forget About This Site" in the right-click context menu of an history item.