How to allow Participant to evaluate performance document after manager evaluation of worker task?

While creating the performance process flow, following task were added:

1. Worker Self-Evaluation
2. Manager Evaluation of Workers
3. Manage Participant Feedback
4. Share Performance Document
5. Provide Final Feedback

The above process flow was attached to the performance template and performance document was assigned to the employee.

After completion of 'Worker Self-Evaluation' and 'Manager Evaluation of Worker' tasks, a participant was unable to provide ratings and comments in the performance document when attempting to complete the 'Participant Feedback' task. Our requirement is for the participant to be able to view the ratings and comments submitted by both the employee and the line manager in the performance document, and then to provide their own ratings and comments.