<blockquote>
<p>I wanted to ask you if this behavior is known to you and you know a solution, or if this is more of a mistake with the broker.</p>
</blockquote>
<p>To connect multiple RIOT instances to the same RSMB broker, you need to use different clients ID. This can be done by editing the <code>EMCUTE_ID</code>, <a href="https://github.com/RIOT-OS/RIOT/blob/master/examples/emcute_mqttsn/main.c#L32">here</a>.</p>
<p>I don't understand your first question.</p>

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