WI-FI lights of the printer are off. How to fix it?

Hello,

I have an XP-225 ,it hasn't an usb cable, so the only way to use it is with Wifi, and it hasn't a screen, so it can not be set directly.

The problem is that the WI-FI lights (green and orange) are off. It seems that the printer is not connected to the rooter.

The rooter is "ON" and many devices are connected to it without any problem. The printer is "ON" and I can do photocopy with it.