Database dont update from gridview templatefield

<asp:GridView ID="GridView7" runat="server" DataSourceID="SqlDataSource6" EnableModelValidation="True" AllowSorting="True" AutoGenerateColumns="False" >

<Columns>

<asp:CommandField ShowEditButton="True" />

<asp:TemplateField HeaderText="Förfallodatum" SortExpression=" Förfallodatum" >

<EditItemTemplate>

<asp:Calendar ID="Calendar1" runat="server" VisibleIndex="4"

SelectedDate='<%# Bind("Forfallodatum") %>'

VisibleDate='<%# Eval("Forfallodatum") %>'>

asp:Calendar>

<asp:TextBox ID="TextBox3" runat="server"

Text='<%# Bind("Forfallodatum") %>'>asp:TextBox>

EditItemTemplate>

<ItemTemplate>

<asp:TextBox ID="TextBox3" runat="server"

Text='<%# Eval("Forfallodatum") %>'>asp:TextBox>

ItemTemplate>

asp:TemplateField>

Columns>

asp:GridView>

UpdateCommand="UPDATE faktura SET Forfallodatum = ? WHERE nr = ?

<UpdateParameters>

<asp:ControlParameter ControlID="TextBox3"

Name="Forfallodatum"

Type="DateTime" />

<asp:Parameter Name="nr" Type="Int32" />

UpdateParameters>

if (!Page.IsPostBack)