Manager should get the notification if anything change in rating

Summary:

Hi Expert,

We have received a requirement from the client that if an Employee and a Manger has been completed thier evaluation and the performance document has been locked. After that calibration team changes the rating of an employee then the manager should get the notification that an employee rating has been changed by calibration and what rating has been changed.

If anyone has worked on this requirement before please let me know how can we achieve this requirement.

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