DLOOKUP Run-Time error 2001 'You cancelled the previous operation'

[MABRUNA62]

Can someone tell me what's wrong with this simple piece of code?

Private Sub Command0_Click()
Dim fanswer As String
Dim fMonth As String
Dim fYEAR As String
Dim billc As Double


fMonth = DatePart("m", DTPicker1)
fYEAR = Right(DTPicker1, 2)

If Len(fMonth) = 1 Then
fMonth = "0" + fMonth
End If


fanswer = Nz(DLookup("[B_FiscalYr]", "Budget", _
"[CustomerID] = '" & fMonth & "' and [B_Year] = '" & fYEAR & "' and [B_Billing_Code] = " & billc), "N/A")
MsgBox fYEAR
MsgBox fMonth
MsgBox billc


If fanswer = "N/A" Then
fMonth = ""
fYEAR = ""
MsgBox " Fiscal Year Not Available"
DoCmd.GoToControl "DTPicker1"
End If
PFiscal = Nz(fanswer, "00-00")
End Sub