A business analyst leaves a voicemail saying an internal stakeholder is upset about not being included before the project began and requests an addition to the requirements traceability matrix. How should the project manager improve the stakeholder relationship?

The project manager should engage the stakeholder to gather more information first. This proactive approach demonstrates a willingness to understand their concerns and helps determine the best course of action. Without understanding the specific nature of their upset or the requested addition, it's difficult to assess the impact or validity. Updating the stakeholder engagement plan might be necessary later, but it's premature without more information. Consulting the project scope document or initiating a change request are also premature; the project manager needs to understand the request fully before determining if it's a scope issue or requires formal change control.