Just wait a few days and re-enter it.
On z-library
Z-Library is an e-book website established in 2009, which provides free downloads of books and articles. Z-Library claims to be the largest digital library in the world.
On the website, unregistered users are limited to download 5 times a day, and after registering and verifying email, they are limited to download 10 times a day (only email is required for registration). Of course, you can also get more downloads and additional functions through the donation website.
Permission for users at all levels to download ZLibrary e-books (from official website):
No account registration, 1 day for free download 5 times.
The registered account is a beginner, and you can download 1 0 times for free within1day.
To become an advanced user through donation, 1 day can be downloaded up to 999 times (depending on the donation amount).
Reference: Baidu Encyclopedia-E-book