This sounds like If on a Winter's Night A Traveller by Italo Calvino.
I wasn't sure if it qualified as SF&F, but it is mentioned on isfdb.
Here's wikipedia's synopsis ("traveler" in the US)
If on a winter's night a traveler (Italian: Se una notte d'inverno un
viaggiatore) is a 1979 novel by the Italian postmodernist writer Italo
Calvino. The narrative, in the form of a frame story, is about the
reader trying to read a book called If on a winter's night a traveler.
Each chapter is divided into two sections. The first section of each
chapter is in second person, and describes the process the reader goes
through to attempt to read the next chapter of the book he is reading.
The second half is the first part of a new book that the reader
("you") finds. The second half is always about something different
from the previous ones and the ending is never explained. The book was
published in an English translation by William Weaver in 1981.
The books begins with what appears to be If on a winter's night a traveller, but chapter 2 continues in the second person.
...Wait a minute! Look at the page number. Damn! From page 32 you've
gone back to page 17! What you thought was a stylistic subtlety on the
author's part is simply a printer's mistake: they have inserted the
same pages twice.
You exchange the book for another copy.
Then from the very first page you realize that the novel you are
holding has nothing to do with the one you were reading yesterday.