There is no mechanism to revisit an implemented compensation event. The idea is you agree the CE and move on - it would massively change the risk profile to both Parties if any CE could be reassessed at any stage if a "mistake" has been identified (and you would need a new definition as to what constitutes a mistake!)
It is a bit like a referee decision in football. They make a decision and that is it, no way of going back - but please note this answer has been written pre-VAR (video assistant referee)!!
It is a bit like a referee decision in football. They make a decision and that is it, no way of going back - but please note this answer has been written pre-VAR (video assistant referee)!!