Error: listen EADDRINUSE: address already in use :::3000
//To find the process id (PID) associated with the port
lsof -i tcp:3000
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
node 44475 chen5 31u IPv4 0x8b1721168764e4bf 0t0 TCP *:strexec-s (LISTEN)
//Then to kill the process
kill -9 44475