how to remove device registration details XG310

Hi School Administrator ,

Thank you for reaching out to the community, please refer = Unable to deregister the Sophos Firewall.

Hi School Administrator If you are referring to Sophos Firewall registration (appliance registration details) and license management, it is now migrated from MySophos into Sophos Central. If you want to change your firewall registration's existing account (company info) to a different account then the below steps will help.

Transfer firewalls between Sophos Central accounts
https://docs.sophos.com/central/customer/help/en-us/index.html?contextId=firewall-transfer-customers

After the successful transfer, the appliance will be part of that new account, and details and name will reflect on the Firewall GUI about the new account (company name)..

Basically, you are the owner of the firewall and SFOS always needs an owner.

What do you want to do? Sell it to someone else?