Arduino Yun, webpage not avaiable

Everytime after configuring to the wifi with arduino Yun, my browser(Chrome) always shows that the webpage is not available(Detail: Google Chrome's connection attempt to was rejected. The website may be down, or your network may not be properly configured.)The API REST is open, and occasionally I can login to the interface by type this address to the browser. Most of the time I have to reset the WLAN and try to configure again.

Could anyone tell me what is going on? Thank you very much