sudo lsof -PiTCP -sTCP:LISTEN
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
GitHub 850 grgarside 6u IPv4 0x23c345381d089301 0t0 TCP localhost:25035 (LISTEN)sudo lsof -i tcp:3000
sudo lsof -nP -iTCP:<YOUR PORT> | grep LISTENlsof -n -i TCP:8080
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
node 54762 user 23u IPv4 XXXXXXXXX 0t0 TCP 127.0.0.1:http-alt (LISTEN)
PID // is second field in the response . Then, kill that process:
kill -9 54762 // here put PID number found on the table 54762