It looks like recent changes made it so you can never get the same scroll twice from the Library of Esoteric Knowledge.
However, once you have already gotten all the scrolls from the Library, the game, in effect, no longer allows you to access it (you get a message like “the library has nothing else to offer you”). So if you have gotten all the scrolls before completing the “Find the Library of Esoteric Knowledge” step in the Adventurer journey, you are forever locked out from completing this step and progressing on this journey.
Please patch this.