I have a problem with raspberry pi 3, Model B conecting Wifi. I have the raspberry 3 display 7" where I can see if wifi is connected.

First of all sorry for my bad english.

When I connect and disconnect raspberry with ethernet wire the wifi works, then when I reboot the wifi works perfectly too, and I can reboot whenever I want and wifi works.

But when the raspberry shutdown and wake up wifi doesn't work.

The file /etc/wpa_supplicant/wpa_supplicant.conf:

 network={
    ssid="My_wifi_name"
    psk="Password"
}

Some idea? If you need another file say me please, I'm little noob.