The project manager should meet with the team member's functional manager to try to remove the impediment that is preventing the team member from completing their user story. The project manager should explain the impact of the delay on the project scope, schedule, and quality, and negotiate a solution that would allow the team member to resume their work on the user story as soon as possible. This approach is consistent with the agile principle of removing impediments and enabling self-organizing teams12. References: 1:
PMBOK Guide, 6th Edition, Chapter 5: Project Scope Management 2: Agile Practice Guide, Chapter 2: An Agile Mindset