Hello Carlos, I'm sorry to hear you're suffering attacks on the XMPP interface. I recommend setting up the Brute-force IDS rules specific to XMPP, and setting these higher than 5 failed attempts. Most chat clients should stop attempting after 3 attempts, so this should prevent legitimate users being blocked. Additionally, you can obtain the public IP address of your critical users and add an entry under Settings>Security>Whitelist as well and this should prevent blocks.