@Gervene 

Good day.

May I know who is your internet service provider?

If you connect the laptop via cable to the modem directly, are you able to get internet service?

--if yes, could you please connect the Deco back, then power off the cable mode; leave it for 5mins and power back the modem to have a look;

 And if the LED is still red, could you please go to more>advanced> internet>what is the internet IP address here?

Thank you very much.