@Elcordones You can change the Deco X20 mode from Router Mode to AP Mode.

  @Elcordones You can give static ip's to your devices from your ISP router also after u use Deco X50 in AP Mode

Elcordones wrote

Good afternoon,

During the process of automating my new home, I asked my internet provider to switch from their Comtrend router to a Nokia ONT so I could manage my entire network from the set-top boxes. Once connected, the ONT has all the green LEDs (internet connection and everything OK), but when I connect the set-top box to the ONT, it doesn't get an internet connection. What could be happening?.

  @Elcordones 

Thank you very much for the feedback

Are the "set-top boxes" here Deco X50 units, or the regular IPTV STB devices?

I think it is more likely due to the internet connection type. Which internet connection type on the Deco you have selected? How about the previous network configurations on the Comtrend router, Dynamic IP or PPPoE, within or without VLAN IDs?

-If there is a wired laptop, you can also connect the laptop directly to the Nokia ONT to test whether the laptop can get an internet connection directly.

It is also recommended to refer to Unable to connect to the Internet for more suggestions.

Wait for your reply.

Best regards.