My XiaoMi14 and my PC is connect to Internet, and I also tried to connect to the internet with or without using VPN, but failed. The phone is not open WIFI and only use cellular network
I have sovled this problem. The key point is that when use USB connect to your PC, it cannot be set to USB network sharing mode, otherwise the POST request can not be successd.
the log is
My XiaoMi14 and my PC is connect to Internet, and I also tried to connect to the internet with or without using VPN, but failed. The phone is not open WIFI and only use cellular network