RunTime error 91 : object variable or with block variable not set

[sukh13]

I am getting Run time error 91 in below ** area.I couldn't figure it out where is the problem. What i try is, to avoid to enter duplicate pin number.

Public Function Custom_PIN(ByVal TableName As String, _
    ByRef EmployeeCode As String, ByVal FieldName As String, ByVal DataToCheck As String, _
    Optional ByVal CodeFieldName As String = Empty, Optional ByVal CodeFieldValue As String = Empty) As Boolean

Dim lstrSQL1 As String
Dim lrsTemp1 As ADODB.Recordset

    lstrSQL1 = " Select  " & FieldName & "  from  " & TableName & " Where PIN_NO =" & DataToCheck & ""
    'MsgBox (lstrSQL2)

    If Len(Trim$(CodeFieldName)) <> 0 And Len(Trim$(CodeFieldValue)) <> 0 Then
       lstrSQL1 = lstrSQL1 & " AND " & CodeFieldName & " <> '" & CodeFieldValue & "'"
    End If

    Set lrsTemp1 = cObjDBConn.ExecuteSQL(lstrSQL1)

    If lrsTemp1 Is Nothing Then
        Custom_PIN = False
    ElseIf Not (lrsTemp1.BOF And lrsTemp1.EOF) Then
        Custom_PIN = True
        lrsTemp1.MoveFirst
        EmployeeCode = lrsTemp1.Fields("EMPLOYEE_CODE")
    ElseIf lrsTemp1.RecordCount = 0 Then
        Custom_PIN = False
    Else
        Custom_PIN = False
    End If

    ***If lrsTemp1.State = adStateOpen Then lrsTemp1.Close
    Set lrsTemp1 = Nothing ****

Exit Function

ErrorHandle:
    Custom_PIN = False
End Function

Here is my calling Code

If gobjValidation.Custom_PIN(fstrTableName, gEmployeeCode, "EMPLOYEE_CODE", _
            Trim$(TxtPINno.text)) = True Then
            MsgBox (gEmployeeCode)