View system port usage

first step:

Win+R opens, enter cmd to enter the command window

Step two:

Enter netstat -ano and press Enter

to find the corresponding process PID is 14472

Or use this method:
use netstat -ntlpto view the listening port, no 3000

third step:

Enter the command tasklist and press Enter

Find the corresponding process name: node.exe

the fourth step:

Open Task Manager, click Details, find the running task according to the found process name and PID, and click End Task

Then restart the program to start normally