Removing a moderator in phpbb...

[slipd]

Hi guys,

I've had a recent shake up of personnel on my forum and I'd like to remove a user as a moderator.

I've followed;

Forum Moderator permissions can be assigned to users by clicking "Users' forum permissions" from your ACP Permissions tab, selecting a user, selecting one or more forums from the list, and then selecting "Moderator permissions" from the Select-type dropdown.

but even after changing their permissions back to 'Not Assigned', they still appear as a moderator on my board...

Any ideas? I'm guessing some kind of global setting has been used in the past? Strange though because no groups are active