If user is part of project manager group then Check for Project manager group whether have Build Team On New Project permission checked or not. Also Check View Resource Center and View Resource Plan permission is checked or not, By default PM group
will have permission.
Build Team on New project is required for building team.
If you are not using PM group and user is not a part of group then give all the three permission to the user mainly Build Team On New Project permission .
If everything seems fine then check the RBS and department for the project manager if you are using RBS and department in PWA.
Also check if any filter has applied.
kirtesh