According to the PMBOK Guide, the project manager is responsible for managing the project team and ensuring that the team members perform their assigned tasks effectively. One of the tools and techniques for managing the project team is interpersonal and team skills, which include conflict management, negotiation, and emotional intelligence. These skills help the project manager to address any issues or problems that may arise among the team members, and to resolve them in a constructive and respectful manner. The project manager should not ignore the problem, move the team member to another task, or involve the whole team without first understanding the root cause of the issue. The best option is to have a confidential discussion with the team member to identify the root cause, and then work together to find a solution that satisfies both parties and supports the project objectives. References: PMBOK Guide, 7th edition, pages 267-268, 271-272.