This issue can happen when the user does NOT have Project - Task Management access to edit tasks on the project but does have view or edit project access. This tab currently does not check for the ‘Project - Task Management’ access right for the user.
Applies to Modern PPM 15.5 (Also referred to as the New User Experience (UX)
This issue is under review
Workaround: Ensure that the user has the ‘Project – Task Management’ access right to allow them to manage tasks on the projects for which they should be allowed to manage.