What is the ruling on money acquired from early retirement after falsifying one's age in order to obtain it?

What the person did in forging his age is forbidden (haram) because it involves lying, cooperating with the court to issue a false testimony, and taking others' money without right. Therefore, one must promptly repent and not take the money. If you have taken it and cannot return it, then donate it as charity. Also, those who assisted him must repent.