thanks for giving a newbie in VBA a little help and guidance.
I am trying to program a macro for conditional formatting in a pivot table(s).
Goal is to find two columns by headers (as their location might change) and apply a conditional formula to one of them. (highlight outlier cells in red)
Headers are in Row 3
Columns starting with A  
Example below:
I want to find the column that has Origin Airport,
then find the column that has Origin Handling,
 create a formula the has 2 conditions to compare,e.g. B4 with B5 (match) and D4 with D5 (match) and then highlight any values in Origin Handling (column D) that are not in line, where D4 <> D5.
The following formula I used to test for consistency "=(AND($B4=$B5,D4<>D5)"  
! [screenshot of the table] (https://i.stack.imgur.com/fhNog.jpg)
I have gone through various posts here on SO and put the codes together that i think are applicable. Being a newbie however I am not getting the correct flow, was trying segment by segment but hit a wall when trying to find a code that provides column Letter by find: Header and then creates a formula. Below code sequence is incomplete.
    Sub Origin_Charges
        ' Review origin charges based on Consistency
        With ActiveSheet.PivotTables("Origin") 'focuses on the Pivot Table I named Origin'
            Dim ws as worksheet
            Dim rngDateHeader As Range
            Dim rngHeaders As Range
        End with
        Set rngHeaders = Range("3:3") 'Looks in entire first row; adjust as needed.
        Set rngDateHeader = rngHeaders.Find("Origin Airport")
            If rngDateHeader is Nothing then "No Origin Airport Column Found"
        Set rngHeaders = Range("3:3") 'Looks in entire first row; adjust as needed.
        Set rngDateHeader = rngHeaders.Find("Origin Handling")
            If rngDateHeader is Nothing then "No Origin Handling Column Found"
        Selection.FormatConditions.Add Type:=xlExpression, Formula1:= _
            "=AND($B4=$B5,D4<>D5)" 'Formula right now is fixed but want it to adjust based on what column Origin Airport is in'
        Selection.FormatConditions(Selection.
        FormatConditions.Count).SetFirstPriority
        With Selection.FormatConditions(1).Interior
            .PatternColorIndex = xlAutomatic
            .Color = 255
            .TintAndShade = 0
        End With
        With Sheets("Origin")
           .Range("D4").AutoFill .Range("D4:D" & .Cells(.Rows.count,"C")
           .End(xlUp).row)
        End With
    End Sub
Any help is greatly appreciated.
 
    