Description of the problem: I checked Consle and found Postman had been frantically trying to link to port 7890, which I didn’t use. Could not send request.
Solution: 1. I installed Postman on my computer and then used the same service port. Check conSLE and find no connection to local port 7890. The two Settings were compared and found the same.
2. However, I always thought it was the problem of setting. Later, I tried to remove the check of setting- proxy-use the system Proxy
 
I guess the local proxy set the pot.