Terminated and Now Facing Recovery Questions: What Can My Friend Do?

My friend got terminated last month. He received an email stating that his Full and Final settlement will be processed from the 9th of December. However, today his manager is inquiring about recovery.

Kindly advise on what he can do in this situation.

What should we do in this case?

The manager is saying that they will speak to HR to process the F&F, but HR is saying that the manager has not given clearance. Nobody has been informed about dues and anything, and almost a month has been completed.

Kindly advise.