This user… has probably lost their Administrator access. There’s nothing special about this user besides its name, and it can lose permissions just as any other user (in the global Administration > Security > Global Permissions)
If no other user had admin access, I suggest reading the documentation on Reinstating Admin Access.
Hi Colin, Thanks, we would try re-instating. But the Administrator user as you see is the Global Super user at the highest level and now none of the IDs are able to see the Administration tab, including the above mentioned super user admin.