What happens when I select "remove" on a phone number in the "unassigned" bucket of my account?

hi boyan,

Zoom support article states:

(Optional) If you want to delete the number and free up a phone number license, go to the Unassigned tab and click Delete next the unassigned phone number.

Zoom does not say what happens when you delete the phone number.  Please see what the Federal Communications Commission says about re-assigning telephone numbers.

Managing phone numbers – Zoom Support

To reduce unwanted and intrusive calls intended for a phone number's previous owner, the Commission [FCC] now requires service providers to regularly report permanent number disconnections and to wait a minimum of 45 days before reassigning a disconnected number to a new user.

Reassigned Numbers Database | Federal Communications Commission (fcc.gov)