Why Did Amazon KDP Reject my Sketch Book for too Many Blank Pages?
They will reject books like this with nothing on them if there are to many consecutive pages that are blank.
You can try adding page numbers to all the pages, and or put title at the top of the page with a line, so the person would have a space to add a title. Or get creative in other ways and add something else to the pages.
There are no guarantee's even they will always accept those even, but it defiantly improves your odds of your book being approved.