Attach close container

Hi guys, i have problem when try access container with the command “docker attach”.

The problem is generated when execute command "docker attach ID’, i press enter and the terminal return to the command line without join to container.

If after this i execute ‘docker ps -a’ see as container was closed and status is “Exited (74)”.

I Attach the output of the ‘docker ps -a’

CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
81a693e30e9c d3 “in.tftpd /bin/bash” 21 minutes ago Exited (74) 20 minutes ago quizzical_liskov