Invalid merge field message although I am using right field names in word document

[aman1234]

Hi Guys

I am writing the following code to print off the word letters but anyhow its saying Invalid merge field, "You want to remove it or replace it"

But I am using right field names in the document. I have checked many times and they are right so not sure why its giving me invalid merge field message every time I run the code.

Private Sub CmdPrint_Click()

Application.DisplayAlerts = False
Call Merge_123
Application.DisplayAlerts = True

          
    MsgBox "The letters have been printed off."

End Sub
Sub Merge_123()
MsgBox "Hello"
 strworkbookname = "J:\WilliamsLea-AIMM\Critical Document Handling\ODH System.mdb"
 
 With CreateObject("Word.Application").Documents.Add("C:\Documents and Settings\kaura2\Desktop\Reference.doc").MailMerge
  .MainDocumentType = 0
  .Destination = 1
  .OpenDataSource _
            Name:=strworkbookname, _
            AddToRecentFiles:=False, _
            Revert:=False, _
            Format:=wdOpenFormatAuto, _
            Connection:="Data Source=" & strworkbookname & ";Mode=Read", _
            sqlstatement:="SELECT * FROM `tblmaster` where Printpoolno='" & ComboBox2 & "'"
  .Execute
  .Parent.Close 0
 End With
 
 MsgBox "The letters have been printed off"
End Sub

Please see attached the word document as well. In the table there are following fields:
Username,Surname,PolicyNo,Printpoolno,QADD,QAMM,QAYYYY

I hope anyone can help me in this.

Thanks