NEW YORK — When recent Columbia grad Christina Egan opened her mail and found a handwritten card addressed to her, she figured it was an invitation from a friend or a holiday card — not her New York state ID she lost a year ago.

As a millennial living in the Lower East Side last year, Egan says she regularly would go out to local bars with no purse or wallet — just her ID, debit card and a tube of lip gloss in her jacket pocket.

When she lost her New York license while out one night, the 23-year-old ordered a new one and thought nothing more of it.

So when Egan opened the letter recently and found the ID, she didn’t know what to think at first.

“When the ID slipped out I was confused because I had forgotten about the situation,” Egan told PIX11. “I thought for a second that I might have been pranked but after asking around I put the pieces together.”

The ID came with an anonymous note thanking Egan for the use the sender got out of the license.

“Found this on the floor of a bar about a year ago, hope you don’t mind I used it for awhile,” the note read. “But — now I’m 21 so you have can it back! Thanks.”

Egan says she thought the situation was “hilarious” and the note was “so sweet, especially with the fancy stationary.”

“I’m sure that ID saw some good times…if only it could speak,” Egan said. “I’m sure it was a college student trying to enjoy her junior year of college.”

However, one part of the story does confuse her — how her ID got all the way upstate. The postage on the envelope was marked from Albany, while Egan lost her ID in Manhattan.

Egan — who just completed her master’s in social work at Columbia in May — says she plans on keeping the second copy of her ID as a backup in case she loses it again.

“I only wish she would have sent the $10 it took to replace (the license),” Egan said. “I hope this mystery girl enjoyed her time as Christina.”