Code works with control button but not with Activate sheet

[Alex B]

Hi,

I run this script with a button within a worksheet:

Sub updatepersonnellist()
   
   Application.Calculation = xlCalculationManual
    
    Application.ScreenUpdating = False
        
    Sheets("Resurstid").Visible = True
        
    Sheets("Resurstid").Select
    Columns("A:F").AdvancedFilter Action:=xlFilterCopy, CriteriaRange:=Range( _
        "H1:M2"), CopyToRange:=Range("H4"), Unique:=True
        
    Sheets("Analys per konsult").Select

                With Sheets("Analys per konsult")


            With .Range("B15:N1000")
            .Clear
            End With

           Dim lastRow2 As Long
            lastRow2 = Sheets("Resurstid").Range("H" & Rows.Count).End(xlUp).Row + 7
            Sheets("Analys per konsult").Range("B12:N12").Copy Sheets("Analys per konsult").Range("B13:N" & lastRow2)
            End With

   Sheets("Resurstid").Visible = False

   Application.Calculation = xlCalculationAutomatic
        
End Sub

With the button, the code works as I want it to. Now I´m trying to put the code in the same worksheets Activate procedure, but then I get the error message: "Run time error 1004: We can´t do that to a merged cell", and the following part of the code is marked:

    Columns("A:F").AdvancedFilter Action:=xlFilterCopy, CriteriaRange:=Range( _
        "H1:M2"), CopyToRange:=Range("H4"), Unique:=True

In the sheet where the advanced filter is done, there are no merged cells.

Any suggestions on what I´m doing wrong?