Hi@SayeemAhmed,

Thank you for contacting our community.

Connection Preference is an auxiliary setting that allows the device to try to connect to the frequency band (such as 5GHz Wi-Fi) or signal source you specify when conditions permit. This is equivalent to giving the device a "suggestion" rather than a hard requirement.

The device will dynamically select the optimal connection based on the real-time environment (such as signal strength, interference, and load conditions). If the preferred signal cannot meet the stability or speed requirements, the device will automatically switch to other available networks to ensure that your user experience is not affected.

  @SayeemAhmed Mixing Deco models NEW + OLD so the Connection Preference could'nt work and all the settings back to default after reboot and could'nt saved. I tried when i had Deco X20 + Deco M4 my Connection Preference of devices could'nt saved and @David-TP Said that this happned because of mixing Deco models.

  @ARGamingPK1 No dear it M4v2 Deco X50v1.30 same condition.

  @Joseph-TP i want just fixed device 5gzh not connect 2.4ghz

  @SayeemAhmed What do u mean?

  @ARGamingPK1 I want to understand that this is not happening on the Deco m4, nor is it happening on the Deco X50, like when I set someone to 5ghz, they will only use 5ghz and will not be able to use 2.4ghz.

  @SayeemAhmed Yeah because you force the device to always connect to 5 GHz so the device will only connect to 5 GHz not gonna connect on 2.4 GHz but to resolve this problem you can separate your SSID for Main WiFi and IoT Network on 2.4 GHz and 5 GHz and give different names.