I have a form to set reminders on it. When I write a 1 reminder, everything works well. But when I write 2 reminders in same time, it comes this message.
(Column 'Reminder_Time' does not belong to table Reminder.)

Actually, I am not sure why this problem comes, and I don't know how I can solve it.

Maybe it's from Timer's code...If so, here it is.

Code:
Dim i As Integer
        TextBox3.Text = DateTime.Now.ToShortDateString()
        TextBox4.Text = System.DateTime.Now.ToShortTimeString
        strsql = "Select Reminder_Time from reminder where Reminder_Date = '" & TextBox3.Text & "'"
        oledbcon.Open()
        Dim cmd As New OleDbCommand(strsql, oledbcon)
        da = New OleDbDataAdapter(cmd)
        ds = New DataSet
        da.Fill(ds, "Reminder")
        dt = ds.Tables(0)
        Dim find As String = cmd.ExecuteScalar
        oledbcon.Close()
        For i = 0 To dt.Rows.Count - 1

            Dim tabl As String = (dt.Rows(i)("Reminder_Time"))
            oledbcon.Close()
            If tabl <> Nothing Then
                If TextBox4.Text = tabl Then
                    Pop.Show()
                End If

            End If
        Next