Mosquitto from remote IP [closed]

I have Mosquitto 2.0.1 on an Ubuntu server. It works fine with the Mosquitto Explorer from an IP on the same subnet. The configuraion file of mosquitto is:

pid_file /run/mosquitto/mosquitto.pidpersistence_location /var/lib/mosquitto/log_dest file /var/log/mosquitto/mosquitto.loglog_type debug error warning notice informationinclude_dir /etc/mosquitto/conf.dlistener 1883allow_anonymous truepassword_file /etc/mosquitto/passwordsprotocol mqtt

On the router the port 1882 is opened, and when I try to connect to the broker I see the packet from the remote IP with tcpdump, but without success. With netstat I see the connection with Syn_RECV state, and it doesn't change.

The firewall is off. How can I debug to understand the problem?