Subscript out of Range ? Run time error 9

Can anyone suggest why I get a subscript out of range error 9 ?

My code is :

Sub CopyDataToSheet2AndMaster()
    Dim wsSource As Worksheet
    Dim wsTarget1 As Worksheet
    Dim wsTarget2 As Worksheet
    Dim lastRow As Long
    
    
    ' Set references to the source and target worksheets
    Set wsSource = ThisWorkbook.Sheets("IncidentsForm")         :mad: ERROR HAPPENS HERE (Subscript out of Range, Run time error 9)
    Set wsTarget1 = ThisWorkbook.Sheets("Incidents")
    Set wsTarget2 = ThisWorkbook.Sheets("IncidentsMaster")
    
    Sheets("IncidentsForm").Select
    
    ' Find the last row with data in column A of Sheet1
    lastRow = wsSource.Cells(wsSource.Rows.Count, "A").End(xlUp).Row
    
    ' Copy data from columns A to X in IncidentsForm to the next available row in Incidents sheet
    wsSource.Range("A3:X" & lastRow).Copy wsTarget1.Cells(wsTarget1.Rows.Count, "A").End(xlUp).Offset(1)
    
    ' Copy data from columns A to X in IncidentsForm to the next available row in IncidentsMaster sheet
    wsSource.Range("A3:X" & lastRow).Copy wsTarget2.Cells(wsTarget2.Rows.Count, "A").End(xlUp).Offset(1)
    
    ' Clear the original data in IncidentsForm
    wsSource.Range("A3:X" & lastRow).ClearContents
    
    ' Optionally, you can clear the clipboard
    ' Application.CutCopyMode = False
    
    ' Print a success message
    MsgBox "Data copied from IncidentsForm to Incidents and Master sheet, and original data cleared."
End Sub

The macro is supposed to copy data in a Table on the IncidentsForm Tab, (Table currently has data in it from A3 to X17, table header is in row 2, and the table is called Input)
I want it to copy into a new line at the bottom of the data in the Incidents tab, and also a copy of the data into the IncidentsMaster tab and then clear the data.

I have triple checked the sheet names, and they are correct, so why is it not able to Set the Worksheet ?

Any idea's ?

Many thanks

Rich