GridView does not display all rows

I have a gridview in my form. I set the DataSource to a DataTable. I am retrieving a DataTable as follows:

SELECT AMOUNT, ISSUEDATE,REASON FROM PAYMENTS WHERE 
PENSIONERID=113 ORDER BY ISSUEDATE DESC

When I run this request on the server side, I get three entries. But on my webpage, gridview shows only two of them. There is no condition in the code that causes gridview not to show any record. After a while, when I restart the server, I see the third row in the gridview. Is this a problem with my IIS? What could be the reason anyway? Thank.

Here is the loading code for the GridView and datat:

<asp:GridView ID="gvOdanBirm" runat="server" AllowPaging="True" 
    AutoGenerateColumns="False" CellPadding="4" ForeColor="#333333" 
    GridLines="None" OnPageIndexChanging="gvPayments_PageIndexChanging" 
    PageSize="3">
    <FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
    <Columns>
        <asp:BoundField DataField="ISSUEDATE" HeaderText="Issue date">
            <ItemStyle BorderColor="#01055E" BorderStyle="Solid" BorderWidth="1px" 
                HorizontalAlign="Right" Width="70px" />
            <HeaderStyle BorderColor="#01055E" BorderStyle="Solid" BorderWidth="1px" />
        </asp:BoundField>
        <asp:BoundField DataField="AMOUNT" HeaderText="Amount">
            <ItemStyle BorderColor="#01055E" BorderStyle="Solid" BorderWidth="1px" 
                HorizontalAlign="Right" Width="30px" />
            <HeaderStyle BorderColor="#01055E" BorderStyle="Solid" BorderWidth="1px" />
        </asp:BoundField>
        <asp:BoundField DataField="REASON" HeaderText="REASON" 
            >
            <ItemStyle BorderColor="#01055E" BorderStyle="Solid" BorderWidth="1px" 
                HorizontalAlign="Left" Width="50px" />
            <HeaderStyle BorderColor="#01055E" BorderStyle="Solid" BorderWidth="1px" />
        </asp:BoundField>
    </Columns>
    <RowStyle BackColor="#F7F6F3" ForeColor="#333333" />
    <EditRowStyle BackColor="#999999" />
    <SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" />
    <PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" />
    <HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
    <AlternatingRowStyle BackColor="White" ForeColor="#284775" />
</asp:GridView>

Code for:

 gvPayments.DataSource=  GetPayments(pensionerID);
 gvPayments.DataBind();