/usr/bin/docker: Resposta de erro do daemon: o driver falhou ao programar a conectividade externa no endpoint app

Executei sudo lsof -i :80 e obtive:

COMMAND  PID     USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
nginx   3336     root    6u  IPv4  21408      0t0  TCP *:http (LISTEN)
nginx   3336     root    7u  IPv6  21409      0t0  TCP *:http (LISTEN)
nginx   3338 www-data    6u  IPv4  21408      0t0  TCP *:http (LISTEN)
nginx   3338 www-data    7u  IPv6  21409      0t0  TCP *:http (LISTEN)
nginx   3339 www-data    6u  IPv4  21408      0t0  TCP *:http (LISTEN)
nginx   3339 www-data    7u  IPv6  21409      0t0  TCP *:http (LISTEN)