XMPP pubsub avatar in ejabberd not working

I'm trying to publish an avatar through a client of my own, android. I'm having problems. However, when I use the xabber client it works perfectly.

This is the packet I'm trying to send:

<iq type="set">
<pubsub xmlns="http://jabber.org/protocol/pubsub">
    <publish node="urn:xmpp:avatar:data">
        <item id="b5ba6aeefccd49006c6a77d4a24c6bb4a87ada2c">
            <data xmlns="urn:xmpp:avatar:data">...content_here_2Q==

Here is the response from the server:

<iq to="mattos.official@ec2-54-200-239-11.us-west-2.compute.amazonaws.com/phone" from="mattos.official@ec2-54-200-239-11.us-west-2.compute.amazonaws.com" xmlns="jabber:client" id="vg0Q+9XmUMhh2rQxGhRjrERGdlxEjbk/1iUVlSaURM97tquqDwJpkmVxlnkF6gNhNsg" type="error" xml:lang="en">
<pubsub xmlns="http://jabber.org/protocol/pubsub">
    <publish node="urn:xmpp:avatar:data" xmlns="http://jabber.org/protocol/pubsub">
        <item xmlns="http://jabber.org/protocol/pubsub" id="b5ba6aeefccd49006c6a77d4a24c6bb4a87ada2c">
            <data xmlns="urn:xmpp:avatar:data">content_here_2Q==</data</item>
    </publish>
</pubsub>
<error xmlns="jabber:client" type="cancel" code="404">
    <item-not-found xmlns="urn:ietf:params:xml:ns:xmpp-stanzas" />
</error>

The ejabberd in version: 17.08