The message [DISCONECT 0] displayed when your server is down.
The messages [CONECT 1] , [DISCONECT 1] displayed when TCP Client is connected/disconnected.
could you please test the TCP Server as Command mode for Advanced port scanner?
because I tested one of port scanner on the internet(https://www.advanced-port-scanner.com/)
that tool tried multiple connection to the Module during the port scan like below.
so, as your Data mode of your module, your module can keep only 1 connection because of Data mode.