Getting Run-time error '1004' when visible row assignment after filter function

Question

I am getting Run-time error '1004', when visible row assignment after filter command. I need to get the row number, after performing Auto filter command. In fact same code was working for other excel sheet.

I need the row number (MNxtRw)after filter command.

Sheets("Sheet1").Select
Columns("A:BR").Select
Selection.AutoFilter
ActiveSheet.Range("$A:$BR").AutoFilter Field:=70, Criteria1:="#N/A"
ActiveSheet.Range("$A:$BR").AutoFilter Field:=3, Criteria1:="FP1"
Range("C1").Select
MNxtRw = ActiveSheet.AutoFilter.Range.Offset(1, 0).SpecialCells(xlCellTypeVisible)(1).Row
Range("BP" & MNxtRw).Select
ActiveCell.FormulaR1C1 = "=VLOOKUP(RC16,'Material Mapping FP1'!C1:C4,2,0)"
ActiveCell.Offset(0, 1).Select
ActiveCell.FormulaR1C1 = "=VLOOKUP(RC16,'Material Mapping FP1'!C1:C4,3,0)"
ActiveCell.Offset(0, 1).Select
ActiveCell.FormulaR1C1 = "=VLOOKUP(RC16,'Material Mapping FP1'!C1:C4,4,0)"
Range(Cells(MNxtRw, 68), Cells(MNxtRw, 70)).Select
Selection.Copy
Range("A2").Select
MBelowRw = Cells(Rows.Count, 1).End(xlUp).Row
If MBelowRw <> 2 Then
    Selection.End(xlDown).Select
    MLastRw = ActiveCell.Row
    Range(Cells(MNxtRw, 68), Cells(MLastRw, 68)).Select
    ActiveSheet.Paste
    Application.CutCopyMode = False
End If