Valid if expression not valid entry

[reggieneo]

Hi,
What is the right expression to allow me to edit the [Name] column?
This expression in valid if is what I am using to limit the name and remove in the list what is already on the list.
All works well until I edit and it is throwing invalid entry. Please assist.

(
  SELECT(
    Dipstick[Pump 1 Attendant],
    AND(
      ([Date] >= [_THISROW].[Date Start]),
      ([Date] <= [_THISROW].[Date End])
    )
  ),
       + SELECT(
    Dipstick[Pump 2 Attendant],
    AND(
      ([Date] >= [_THISROW].[Date Start]),
      ([Date] <= [_THISROW].[Date End])
    )
  )
        + SELECT(
    Dipstick[Cashier],
    AND(
      ([Date] >= [_THISROW].[Date Start]),
      ([Date] <= [_THISROW].[Date End])
    )
  )

)
    -
Select(Salary[Name],AND(
      ([Date Start] >= [_THISROW].[Date Start]),
      ([Date End] <= [_THISROW].[Date End]),True))