About RED unlock code
A RED unlock code allows the provisioning servers to accept a new configuration for a RED. It prevents a RED that is in use from being accidentally or maliciously redirected.
If you're configuring a RED for the first time, leave the unlock code blank. If the device has been set up previously on another Sophos firewall, type the unlock code.
When you add a RED to the firewall, the firewall uploads the RED configuration to the provisioning server. The provisioning server then generates an unlock code for that RED and shows it in the web admin console of Sophos Firewall. It also sends the code to the email address you provided when you turned on the RED provisioning service. If you move the RED to a new firewall, you must enter the old unlock code to register the RED to the new firewall.
From SFOS 18.5 MR5, when you delete a RED interface from the web admin console, the console shows the unlock code in a pop-up message confirming the delete action. It also sends the code to the email address you provided when you turned on the RED provisioning service. Make sure the email address you provided on System services > RED is up to date and accurate.
Retain the unlock code. You'll need the code if you want to set up the RED on another firewall.
If you can't find the unlock code, contact Sophos Support.