Just now Mark Smith, 1 Scotland Street appears in the duplicate report as a potential duplicate to Mark Smith, 2 London Road and the database administrator marks them as Not A Duplicate because of the different address and lack of info to know whether they are a duplicate. This clears them off the duplicates list. However, following a mailing to Mark Smith, 1 Scotland Street we find out that he has moved to 2 London Road. That record is amended without awareness that there is already a Mark Smith at 2 London Road on the database. When a duplicate report is run though there are now two Mark Smiths at 2 London Road, they do not appear in the duplicate report because they were once marked as Not A Duplicate when their addresses were different and we didn’t have enough info to know for sure.

When a duplicate report is run it should check for all records that have also had their address changed in case it now matches another record.