: Before the account is deleted or blocked, take high-resolution screenshots of the profile, its URL, and any messages. Note the unique Profile ID found in the URL or page source.
If lookups and OSINT tools yield no results, you can attempt to log the IP address of the person operating the account. This requires getting the user to click a external link. How IP Tracking Works how to trace dummy account in facebook
Instead of tracing a dummy account targeting you, focus on containment: : Before the account is deleted or blocked,
Contact local police or report the harassment to the FBI Internet Crime Complaint Center (IC3) 1.2.3 . take high-resolution screenshots of the profile