Update command in gridview doesn't work.

<%@ Page Language="VB" MasterPageFile="~/_m/nonavbars.master" AutoEventWireup="false" CodeFile="jz_trucks.aspx.vb" Inherits="_a_jz_trucks" title="CPI Intranet | GR-JZ Shuttle Trucks" %>
<asp:Content ID="Content1" ContentPlaceHolderID="cphMain" Runat="Server">
        <h3>Juarez ICT Truck Shipments</h3>
        <h4>Add a new truck shipment</h4>
        Leave Date:&nbsp;<asp:textbox id="txtLveDate" runat="server" tabindex="1" validationgroup="truckInsert"></asp:textbox>&nbsp;
        <asp:imagebutton id="ibtnLveDate" runat="server" imageurl="~/_i/calendar.png" tabindex="2" />
        <asp:requiredfieldvalidator id="reqLveDate" runat="server" controltovalidate="txtLveDate"
            errormessage="*" validationgroup="truckInsert"></asp:requiredfieldvalidator><br />
        Arrive Date:&nbsp;<asp:textbox id="txtArvDate" runat="server" tabindex="3" validationgroup="truckInsert"></asp:textbox>&nbsp;
        <asp:imagebutton id="ibtnArvDate" runat="server" imageurl="~/_i/calendar.png" tabindex="4" />
        <asp:requiredfieldvalidator id="reqArvDate" runat="server" controltovalidate="txtArvDate"
            display="Dynamic" errormessage="*" validationgroup="truckInsert"></asp:requiredfieldvalidator><br />
        Status:&nbsp;<asp:dropdownlist id="ddlStatus" runat="server" validationgroup="truckInsert">
            <asp:listitem>Choose a status.</asp:listitem>
            <asp:listitem>Planned</asp:listitem>
            <asp:listitem>Firm</asp:listitem>
            <asp:listitem>Shipped</asp:listitem>
        </asp:dropdownlist>&nbsp;<asp:requiredfieldvalidator id="reqStatus" runat="server"
            errormessage="*" controltovalidate="ddlStatus" initialvalue="Choose a status." validationgroup="truckInsert"></asp:requiredfieldvalidator><br />
        Initials:&nbsp;<asp:textbox id="txtInitials" runat="server" maxlength="3" tabindex="5" validationgroup="truckInsert"></asp:textbox>&nbsp;
        <asp:requiredfieldvalidator id="reqInitials" runat="server" controltovalidate="txtInitials"
            display="Dynamic" errormessage="*" validationgroup="truckInsert"></asp:requiredfieldvalidator><br />
        <asp:linkbutton id="lbtnJzTrkSubmit" runat="server" tabindex="6" validationgroup="truckInsert">Submit</asp:linkbutton>&nbsp;
        <asp:linkbutton id="lbtnJzTrkReset" runat="server" tabindex="7" causesvalidation="False">Reset</asp:linkbutton>&nbsp;
    <asp:label id="lblTruckSubmitted" runat="server" forecolor="#00C000" visible="False"></asp:label>
    <asp:label id="lblNow" runat="server"></asp:label><h4>Future Shipments</h4>
    <asp:gridview id="grdJzTrucks" runat="server" autogeneratecolumns="False" cellpadding="4" cssclass="jz_truck" datasourceid="srcJzTrucks" forecolor="#333333" gridlines="None" emptydatatext="There are no scheduled shipments." autogenerateeditbutton="True">
        <footerstyle backcolor="#990000" font-bold="True" forecolor="White" />
        <rowstyle backcolor="#FFFBD6" forecolor="#333333" />
        <pagerstyle backcolor="#FFCC66" forecolor="#333333" horizontalalign="Center" />
        <selectedrowstyle backcolor="#FFCC66" font-bold="True" forecolor="Navy" />
        <headerstyle backcolor="#990000" font-bold="True" forecolor="White" />
        <alternatingrowstyle backcolor="White" />
        <columns>
            <asp:boundfield datafield="id" headertext="id" insertvisible="False" sortexpression="id"
                visible="False" />
            <asp:boundfield datafield="leave_date" dataformatstring="{0:d}" headertext="Leaving"
                sortexpression="leave_date" />
            <asp:boundfield datafield="arrive_date" dataformatstring="{0:d}" headertext="Arriving"
                sortexpression="arrive_date" />
            <asp:boundfield datafield="initials" headertext="Submitted By" sortexpression="initials" />
            <asp:boundfield datafield="submit_date" dataformatstring="{0:d}" headertext="Submit Date"
                sortexpression="submit_date" />
            <asp:boundfield datafield="status" headertext="Truck Status" sortexpression="status" />
        </columns>
    </asp:gridview>
    <asp:sqldatasource id="srcJzTrucks" runat="server" connectionstring="<%$ ConnectionStrings:conIntranet %>"
        selectcommand="SELECT [id], [leave_date], [arrive_date], [submit_date], [initials], [status] FROM [jz_truck] WHERE ([arrive_date] >= @arrive_date)" updatecommand="UPDATE jz_truck SET leave_date = @leave_date, arrive_date = @arrive_date, submit_date = @submit_date, initials = @initials, status = @status WHERE (id = @id)">
        <selectparameters>
            <asp:controlparameter controlid="lblNow" name="arrive_date" propertyname="Text" type="DateTime" />
        </selectparameters>
        <updateparameters>
            <asp:parameter name="leave_date" />
            <asp:parameter name="arrive_date" />
            <asp:parameter name="submit_date" />
            <asp:parameter name="initials" />
            <asp:parameter name="status" />
            <asp:parameter name="id" />
        </updateparameters>
    </asp:sqldatasource>
            <ajaxtoolkit:calendarextender id="calxLveDate" runat="server" popupbuttonid="ibtnLveDate" targetcontrolid="txtLveDate">
        </ajaxtoolkit:calendarextender>
        <ajaxtoolkit:calendarextender id="calxArvDate" runat="server" popupbuttonid="ibtnArvDate" targetcontrolid="txtArvDate">
        </ajaxtoolkit:calendarextender>
        <ajaxtoolkit:textboxwatermarkextender id="wtrLveDate" runat="server" targetcontrolid="txtLveDate" watermarktext="Enter leave date.">
        </ajaxtoolkit:textboxwatermarkextender><ajaxtoolkit:textboxwatermarkextender id="wtrArvDate" runat="server"  watermarktext="Enter arrive date."
            targetcontrolid="txtArvDate">
        </ajaxtoolkit:textboxwatermarkextender>
        <ajaxtoolkit:textboxwatermarkextender id="wtrInitials" runat="server"  watermarktext="Enter initials."
            targetcontrolid="txtInitials">
        </ajaxtoolkit:textboxwatermarkextender>
        <ajaxtoolkit:maskededitextender id="meeLveDate" masktype="Date" mask="99/99/9999" runat="server" targetcontrolid="txtLveDate">
        </ajaxtoolkit:maskededitextender>
        <ajaxtoolkit:maskededitextender id="meeArvDate" masktype="Date" mask="99/99/9999" runat="server" targetcontrolid="txtArvDate">
        </ajaxtoolkit:maskededitextender>
</asp:Content>

                                  

1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:
13:
14:
15:
16:
17:
18:
19:
20:
21:
22:
23:
24:
25:
26:
27:
28:
29:
30:
31:
32:
33:
34:
35:
36:
37:
38:
39:
40:
41:
42:
43:
44:
45:
46:
47:
48:
49:
50:
51:
52:
53:
54:
55:
56:
57:
58:
59:
60:
61:
62:
63:
64:
65:
66:
67:
68:
69:
70:
71:
72:
73:
74:
75:
76: