The project manager should reinforce the value of documenting and approving all change requests and ask the customer to issue these through the agreed channels. This is because change requests are formal proposals to modify any aspect of the project and should follow the change management plan, which defines how changes will be monitored, controlled, and approved. The project manager should also communicate with the project team member and remind them of the change management process and their roles and responsibilities. This will help prevent unauthorized changes that could impact the project scope, schedule, cost, quality, or risk. The project manager should also update the issue log and the lessons learned register to document the incident and the actions taken. References: (Professional in Business Analysis Reference Materials source and documents)

PMBOK® Guide, 6th edition, Section 4.6.1, “Perform Integrated Change Control: Inputs”

PMBOK® Guide, 6th edition, Section 4.6.3.1, “Perform Integrated Change Control: Outputs - Change Requests”

PMBOK® Guide, 6th edition, Section 4.6.3.2, “Perform Integrated Change Control: Outputs - Project Management Plan Updates”

PMBOK® Guide, 6th edition, Section 4.6.3.3, “Perform Integrated Change Control: Outputs - Project Documents Updates”

PMI-PBA® Guide, 1st edition, Section 6.3.1, “Trace Requirements: Inputs”

PMI-PBA® Guide, 1st edition, Section 6.3.2, “Trace Requirements: Tools and Techniques”

PMI-PBA® Guide, 1st edition, Section 6.3.3, “Trace Requirements: Outputs”