From what I see, there are 4 5 options on annas-archive.org
Use fast(but fee charging) direct download
Use ipfs
use torrents
Go to source pages (libgen and/or zlibrary)
Slow direct download [Edited]
It sounds like you clicked the link to the source as opposed to the mirrors
Sneakernet is getting worse and worse these days, I’m learning the ancient art of astroprojecting into random people’s rooms to consume media.