Who is Nia's biological father?

Nia- "I can't think of any--"

"How many number were carved in tattoo of your mentor?"

"Three" Then the number couldn't be that. 

Mr. Oliver wanted Nia to be here, the box was found with the code. The number should be related to Nia. Her birthdate couldn't be used as her actual birthdate and in the official papers were different.

"Do you know anything about that tattooed number?"

"No, he never told." Nia replied with confidence

Should I hack the box or stop the bomb? But both the passcode and bomb were interlinked so it could be a problem. 

Suddenly I remember the message. The clues for passcode could be there beside that number.

"Nia show me that last message once again." She handed her phone .

As I looked into it the four number could be either the time, the date or the year. I told them my specticulation. I could use it as a test for them too.i am lazy to use my mind.