Run-Time Error '424' "Object Required"

Sub trial()
Dim Station_2 As Variant
Dim VCLength_2 As Variant

If Range("$I$3") = "VC" Then
If Range("$I$2") = "GB" Then
If Target.Count > 1 Then Exit Sub
    ActiveSheet.Unprotect ("password")
    Application.EnableEvents = False '<-- Stops the code re-triggering
    Select Case Target.Address
        Case "$J$2", "$F$4", "$F$6"
            If Range("$J$2") = "OVERLAP" Then
             Do
                Station_2 = InputBox("Your GB STATION overlaps into previous Vertical Curve. Try another Station")
                If Station_2 = "" Or Not (IsNumeric(Station_2)) Then _
                MsgBox "TRY AGAIN"
                Loop Until IsNumeric(Station_2) And Station_2 <> ""
                Range("F4") = Station_2
            
            End If
        Case Else:
    End Select
    Application.EnableEvents = True '<-- Turn 'Events' back on
    ActiveSheet.Protect ("password")
ElseIf Range("$I$2") = "VC" Then
If Target.Count > 1 Then Exit Sub
    ActiveSheet.Unprotect ("password")
    Application.EnableEvents = False '<-- Stops the code re-triggering
    Select Case Target.Address
        Case "$J$2", "$F$4", "$F$6"
            If Range("$J$2") = "OVERLAP" Then
             Do
                VCLength_2 = InputBox("Your VC LENGTH overlaps into previous Vertical Curve. Try another Length")
                If VCLength_2 = "" Or Not (IsNumeric(VCLength_2)) Then _
                MsgBox "TRY AGAIN"
                Loop Until IsNumeric(VCLength_2) And VCLength_2 <> ""
                Range("F6") = VCLength_2
            
            End If
        Case Else:
    End Select
    Application.EnableEvents = True '<-- Turn 'Events' back on
    ActiveSheet.Protect ("password")
End If
End If
End Sub