SUMIFS not matching blank values

Question

Hoping someone could please help me with the below, I am using the SUMIFS formula in my VBA code and it works for values except for when i am trying to find blanks.

Example source dataset:

Date (column G in original sheet)	Customer (column O in original sheet)	TransactionValue (column E in original sheet)
2021-02-26 05:45:00 GMT		100
2021-02-26 05:45:00 GMT	JohnDoe	20
2021-02-26 07:12:18 GMT	JohnDoe	15
2021-02-26 07:12:18 GMT		75
2021-02-26 12:22:55 GMT	JaneDoe	28
2021-02-26 12:22:55 GMT	Joe Blogs	85

I am then basically building something that looks a little like a pivot table, with the desired output being the total for each customer for each timestamp:

Date		JohnDoe	JaneDoe	Joe Blogs
2021-02-26 05:45:00 GMT	100	20
2021-02-26 07:12:18 GMT	75	15
2021-02-26 12:22:55 GMT			28	85

below is my code:

Dim r as Range
Dim finalcolumn as Long

finalcolumn = ActiveSheet.Cells.Find("*", SearchOrder:=xlByColumns, SearchDirection:=xlPrevious).Column

Set r = Cells(2, 2)
With r
 .Formula = "=SUMIFS(Results!$E:$E,Results!$O:$O,Static2!B$1,Results!$G:$G,Static2!$A2)"
 .AutoFill Destination:=Range(Cells(2, 2), Cells(2, finalcolumn))
End With

My issue is that this doesn't return anything for the second column, i.e. where Customer is blank. It works fine for all other customer names.

Any ideas please?