Mate um processo olhando a porta no Windows
//Open command prompt and run the following commands
C:\Users\username>netstat -o -n -a | findstr 0.0:3000
TCP 0.0.0.0:3000 0.0.0.0:0 LISTENING 3116
C:\Users\username>taskkill /F /PID 3116
//here 3116 is the process ID
Vivacious Vendace