Hi @amyharkus86 ,
If you are using a gallery, you can replace the hardcoded text with dynamic content like below -
With({varT: ThisItem.ColumnName},Concatenate(Left(varT,2),"-",Mid(varT,3,2),"-",Right(varT,2)))
And when the value is blank you can add a condition -
If(IsBlank(ThisItem.ColumnName, "##-##-##", With({varT: ThisItem.ColumnName},Concatenate(Left(varT,2),"-",Mid(varT,3,2),"-",Right(varT,2))))