User has been assigned Publishing Editor, this was assigned by being a member of a group, where group's permission is publishing editor. 

In addition, the user has been assigned Reviewer, this also was assigned by being a member of a group, where group's permission is Reviewer. 

The issue: The user can only perform functions related to the Reviewer role, and can't perform functions available via the Publishing Editor.

Any Ideas what is going on? 

*Removing the user from the Reviewer group is not an option. 

Hi,

The easiest way is to grant the single user Publishing Editor permission of that folder directly, check if the issue persists.

Right click on the folder, Properties -> Permissions -> Add the user with Publishing Editor permission.

Regards,