I understood now, as the EID(Employee Id) was the key it worked for the EID column. I updated the same for Identifier and Username column and it worked perfectly. Thank you so much for the help!!

Hello,I need help preventing duplicate for 3 fields. Per the suggestion given above, I used the below validation statement=COUNT(SELECT(Items[Name], AND([Name] = [_THIS], [Name]<> [_THISROW].[Name]))) = 0and it prevented duplicate for 1 field, but th...