Unable to add printer in CUPS with "Unauthorized" error in Web browser

Issue

• We are trying to add a printer using the CUPS Web user interface, but we get the following error in the browser:

  

  and the CUPS error log contains:

  E [27/Jul/2022:09:57:12 +0800] [CGI] CUPS-Get-Devices request failed with status 1000: Unauthorized
  

• I can get into the CUPS site to see added devices, but cannot do anything within the site. I am getting "Unauthorized" errors when working in CUPS that I wasn't when first installed even logged in as root.