npm run address already in use

Have you ever got the following error when running laravel mix using npm run hot?

Error: listen EADDRINUSE: address already in use

To fix it, open your terminal and run the command:

sudo lsof -i :8080

This will list processes using that 8080 port. Copy the id and kill the process by running the command:

kill -9 PROCESS_ID

Next up, just re-run npm run hot, and the error should be gone.