Duplicate National Identifier Checks all Person Records

We have enabled profile option for National Identifier Uniqueness Validation Mode to error as we do not want duplicate worker records created. We have found that this is also checking all person records in our database, including people to cover under benefits. We do hire family members at certain locations where people need to be set up under their benefit plan and also as an employee with the same national identifier number. Have any other customers gotten around this issue?