Why do Korean stars write the date of birth on some materials, with the actual date next to it?

Their birthdays are all filled in according to the household registration book.

And the date filled in their household registration book is the date when they actually declare their household registration.

Not their real birthdays.

That's why this is happening.

Li Minyu (usually translated as Yu Min), like a myth, was born in 79.

Myth ranks second. But it took him 80 years to pay the bill. So the file also says 80 years.

And the time of enlistment was delayed accordingly.

That's why Eric and Dane Jin Dongwan, the first to join the army, ranked first and third.