Macro Error 9

Hi,
I am getting error 9 while run macro, this coding was some1 else, now that person left organization and I am unable to resolve it, please guide solution
error line is : -

Del Worksheets("GTB AUDIT"), "GTB", wb

addn:

If h = 1 Then lr = Range("GTB").Rows.Count + 9
If h = 2 Then lr = Range("NGTB").Rows.Count + 9
Set Gcell = wb.Sheets(InputSheet).Cells.Find(GetVal(CStr(Area(x, j))))
GCA = Gcell.Address(ReferenceStyle:=xlA1, _
                RowAbsolute:=False, ColumnAbsolute:=False)
Range("B" & lr).Value = i
Range("C" & lr).Value = "01-" + headers(1, j) + "-" + Year
'Range("D" & lr).Value = i
Range("G" & lr).Value = Area(x, 15)
Range("H" & lr).Value = Area(x, 16)
Range("I" & lr).Value = Area(x, 14)
Range("E" & lr).Value = Area(x, 17)
Range("J" & lr).Value = Now()

wb.Sheets(InputSheet).Range(GCA).Copy Range("D" & lr)
Range("D" & lr).Font.Size = 9
Range("D" & lr).Font.Name = "Calibri"
End If
nxtc:
Next j
Next x
Erase Area, headers
nw:
Next i
Next h
Del Worksheets("GTB AUDIT"), "GTB", wb
Del Worksheets("NOT GTB AUDIT"), "NGTB", wb
Ordering
FormatGTB Sects
FormatNGTB Sects
wb.Close False
Application.ScreenUpdating = True
'ActiveCell.MergeArea.Rows.Count
End Sub