Opening a MenuItemBinding into an iframe

Hello everyone!
I hope you all are doing fine.
I have a MenuItemBinding item, binded to an XML file that gets the information from my SQL server. this is the pieces of code i am using:
<asp:MenuItemBinding DataMember="MenuHijo" NavigateUrlField="URL" Target="hsides" TextField="Titulo" /> I also have an iframe control, the code is:
<iframe id="hsides" runat="server" /> Both are located into mi masterpage.
The problem is that when I click on any item on the menu, it opens in a new tab and not into the iframe.
What am I doing wrong?
Thanks in advance

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