I am a lazy boy. I opened a book directly using the e-book viewer and marked it, including highlighting and tags. I found that moving the storage location of the book and then opening it. The tags in the books in Azw3 and Mobi formats are missing, while the tags in Epub format are still exist. Interestingly, When I moved the book back to its original position, the tags in the Azw3 and Mobi format books were visible again. I don't know if anyone knows why, or am I the only one in this situation.
