Am looking for Bernice Ayivor her address is P.O.Box (removed for privacy) does she exist?

Can you say why you want to find her, what country, and city?

If you are in the US, you sign up and pay for an internet service that specializes in finding people.

"Does she exist" means you've never met her, so no, the odds that she doesn't exist are 99.99%.
She might be a man, 5 men, a married couple, a crime syndicate... all with the same aim, to get your MONEY!

The prime reason people use Post office boxes is to not reveal their home address. Might be home based business reasons... might be because of mail theft and they travel a lot, might be because they have something to hide from everyone but the authorities...

But as was mentioned if you have some sort of "love interest" in her or she's not in the country you reside... odds are she isn't who she pretends to be.