Help with error run-time error '9" (subscript out of Range)

Hello All,

this is in regards to my previous post

https://www.excelforum.com/excel-gen...heet-name.html
Im using the code below but when Im Adding, Deleting rows it keep showing me the error.

Private Sub Worksheet_Change(ByVal Target As Range)

If Intersect(Target, Range("$B:$C")) Is Nothing Then Exit Sub

Dim Lot1() As String
Dim Lot2() As String


Lot1 = Split(Cells(Target.Row, "B"), " ")
Lot2 = Split(Cells(Target.Row, "C"), " ")
Sheets(1).Name = Lot1(UBound(Lot1)) & " vs " & Lot2(UBound(Lot2))

End Sub

Please help me to remove the popping up error.
Attached is the file that Im using.


Thank you