@thejumpingroach Hi, welcome to our community. It is a pity that we can not open your picture. But luckily, you have described the problem quite clearly. If you have swapped the problematic Deco with...

@Davka Hi, thanks for posting question here. It is suggested to share the information about your network topology and detailed needs first. Then we will take further confirmation.

@osmanu Hi, to assist you efficiently, I've forwarded your case to the TP-Link support engineers who will contact you with your registered email address later. Please pay attention to your email box...

@Andrasd Hi, thanks for your further explanation. You may also consider add unmanaged switch in the Deco network. And this guide is for your reference. Happy new year!

@jijookhier Hi, the extension of domain name is not supported. Happy new year~

@Yeong Hi, it is suggested to swap this Deco with your main Deco X50 to confirm whether the problem still follows this Deco: How to replace the main Deco with another Deco You may also change...