Cleo event cannot proceed. After going through the library for the first time, you can no longer access it. she keeps sleeping
You mean with the bubbles on the right with options for reading room and other? then thats a bug...
If you are on PC version, the fix is available in discord channel (just a few MB) Click on the tsukiko's image above to join discord,
But if you are on apk, redownload the apk, dev has updated that file.