I have secured a Room but everyone can still see it?

When you apply Room permissions the default is to provide Read only access to all users other than those allocated with Read/Write access or as the Room Owner.

To completely secure a Room so only the people allocated with access can see it, you will need to un-tick the box Readable to all users at the bottom of the Add Users List.

NOTE:  You can not untick this option when applying Room permissions to the Incident Map room as this is official view of an Incident and will be used by all users for Situational Awareness.