Microsoft project management software used to plan, manage, and communicate a project schedule and other information among workgroup members, project managers, and other stakeholders.
Just seen a similar issue in our Org. A user does not need Planner Plan 1 or Planner Plan 3 to view premium plans shared with them but they do need the Project for Office service enabled in the E3 or E5 license.
In your license group (or direct assignment) check the enabled services and ensure this box is checked.