Hi @jorifree The simple way is to push the WLAN or WiFi button for about a second. On a Huawei HG659 it's on the right hand side, on a TP-Link VR1600v it's located on the top.
To switch it back on simply push the same button, the LED's on the front of the router will show either green for enabled or be unlit for disabled. If you need more help let us know.
I ran initial tests on your service and it shows connected for 1week 2d 13h 1m. Does the service get disconnected when the WAN light went off?
I highly recommend to turn off the modem/router for 2-3mins and turn it back on, by doing this all hardware functions of the modem/router will also refresh the connection of your service to our network.
Tell me how it will go.