saving multiline textbox

 hi All,
I have a txtbox like this:
<asp:TextBox TextMode="MultiLine" Rows=24 ID="TxtOpmerkingen" runat="server" BorderStyle="None" Height="100%" Width="100%"></asp:TextBox></td>
 
I save it into a nvarchar(max) field but it does not seem to be complete. What am I doing wrong?
Thanks
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