Lost typo.

Lately I've been reading this one highly regarded book on trauma that a colleague from my doctoral program who's into social work has been gushing about for years and that I remembered about and put in a library request for recently, when I'd seen somewhere that it was a New York Times bestseller, which I hadn't known. Anyhow, it's great, and I've also found a few typos in it, including in the author bio on the inside flap of the back cover. And so, like I've been doing lately, I've been making sure to go get a pencil and gently correct them. Only, a few weeks ago, I found a typo in a part that I was reading right before I went to bed, only I decided for some reason not to fold the page down there so I could go back to it and mark it whenever I had a pencil with me next, but then I went and didn't read the book for a few days on end, so when I finally started reading again and remembered about the typo, I flipped back through the pages I'd read recently, only I couldn't find it again. I guess that's life?