I tried reopening Legend of the Dragon King after I logged into my account from another phone. I've deleted and added but still and i can't open even after i search using 'explore' and tapped on "read now"
Can't open a book
Have you tried opening other novels beyond the one you tried?
If not you might be the victim of a phantom book, what I mean is that the creator has removed all its chapters, all that's left is the cover so theres nothing to read, to double check should try opening it from your pc, might just be a case of the app crapping itself in some new fun way.