Error writing values to table

[NeoFax]

I have a form with 2 subforms. The main form is used to delimit the
1st subform and then the 1st subform on change updates the 2nd
subform. If there is no discrepancy in the second subform and the
technician wants to input one, he/she types in the info and then
selects the next record in the 1st subform. My problem is that the
below code does not work using the OnExit event of the 2nd subform.
Here is my code:

Private Sub subfrmIssues3_Exit(Cancel As Integer)
Dim tmpHelo As Double
Dim tmpStation As String
Dim tmpJCNum As String

tmpHelo = Forms.frmIssues.subfrmIssues2.Form.txtHelo
tmpStation = Forms.frmIssues.subfrmIssues2.Form.txtStation
tmpJCNum = Forms.frmIssues.subfrmIssues2.Form.txtJCNum

MsgBox ("Helo=" & tmpHelo & " and Sta=" & tmpStation & " and JC=" &
tmpJCNum)

strWhere = "[HELO#]=""" & tmpHelo & " and [STAGE#]=""" & tmpStation &
" and [JobCard#]=" & tmpJCNum & """"

If IsNothing(DLookup("[HELO#]", "tblIssues", strWhere)) Then

Set dbs = CurrentDb
dbs.Execute "INSERT INTO tblIssues ([HELO#],[STAGE#],[JobCard#],
[Discrepancy]) " & _
"VALUES (" & tmpHelo & ", '" & tmpStation & "', '" & tmpJCNum & "',
'" & Forms.frmIssues.subfrmIssues3.Form.txtDisc & "')"

End If

End Sub

Any help would be appreciated.