Rule #1 (before you make things worse
) Read the FAQ
Rule 1b Ask here for advice INCLUDE a good description of you existing setup that is causing issues you are asking about.
In your case: What CLOUD. What OS? And What Calibre version?
Help with starting using a different Library:
See the command line
calibre --with-library
https://manual.calibre-ebook.com/gen...n/calibre.html
That should give you a chance to use the GUI to change Libraries more permanently.