BillionGraves has a duplication program implemented. If you find two duplicate records:
Set each record exactly the same (Make the Vital Information the same. This includes Name, Family Name, Birth, and Death).
Reload the page of the record and if each record is exactly the same a merge arrow will appear near the plus icon.
Select Merge Arrow (will appear next to the plus icon)
Note: The only records that can be merged are the records uploaded using the BillionGraves application. Any duplicate supporting record (record added without using the application) will need to be removed.