Mosquitto MQTT broker log message parsing

I need help on parsing the mosquitto mqtt broker log message.

parsing message: 2024-11-15T11:23:03: New connection from 172.17.0.2:41779 on port 1883.
the connection match is : None
the disconnection match is : None
parsed data received is : None
Message parsed failed
log message from topic $SYS/broker/log/N: 2024-11-15T11:23:03: Client disconnected, not authorised.
parsing message: 2024-11-15T11:23:03: Client disconnected, not authorised.

here I have already written a code which tries to parse the above log message but when i try to run it I’m getting the following
the connection match is : None
the disconnection match is : None
parsed data received is : None
it is not able to read and parse the log message. can you please help on this.
Thank you