@Dinu_ks 

if i disable smart connect and keep same ssid for 2.4 & 5ghz then also my devices prefer 2.4ghz as default

  @Sunshine 

poco f5 and mi11x facing this issue only with the mentioned routers, every other routers connects without issue

yes i've tried that. 5ghz is working perfectly fine. only issue is with smart connect. why it prefers 2.4 instead of 5g?

  @Dinu_ks As far as I know it´s the client who decides what is the best available network. That being said you may want to try a workaround that did work for me for a couple of weeks.

I have an Archer C80 v1 (US) with the latest firmware released this week and the only phone/device that I´m aware is having your same issue is my own Moto G200. All other devices are connecting to 5Ghz when they are close enough to the router and switching automatically to 2.4Ghz when they are a bit too far, except the phone mentioned which is always hooked up to 2.4Ghz.

Since you are aware already that you are connected to 2.4 Ghz and not 5 Ghz I would assume that you already know how to see the connection properties... from there click the "Edit" button in the top right corner and go to the "Advanced Settings". You can try changing the methered connection settings (sorry my Android is in Spanish and I´m not sure how to phrase it properly) but what you´re most interested in is the "Privacy". For security reasons most Android devices will randomly change their MAC Adress when connecting to a Wireless Network. Being this your own house/network I don´t see how this would be a problem but try using the option that says something like "use device´s MAC". Save the changes and check how it goes.

Hope it helps!

  @Archundias nothing helps me out.. developers must work hard to make smart connect usable.  

Just a name with features "smart connect" but relatively not useful for most..

I had never faced any issue with other brands. Infact there also i have same ssid for both 2.4 and 5ghz and wifi switches flawlessly .

And most suggesed solution for smart connect I've seen in forum is to keep seperate ssid. If that is the case what is the use of smart connect then.

Ive done all possible r&d accross internet and nothing helped me out to fix this..  hope some algorithms will be done to fix this

  @Dinu_ks 

@developers .  is there any fix you found for smart connect issue.. its really annoying.. my friend purchased ax10 yesterday. his most devices creating issue with smart connect.

if this was designed to connect the radio only to 2.4ghz. then its not required.. and what is the purpose in purchasing dualband and tri band routers.

none of the otherbrand has this issue, other than tp link.. 

  @Dinu_ks 

When you disable smart connect and set the same SSID for both bands, the two phones still prefer 2.4G WiFi by default, which must be the behavior of the client, since smart connect has already been disabled.

  @Dinu_ks  any solution will be much appreciated. 

  @Dinu_ks 

guess tplink itself dont have the answer to over come this issue. can you guys fix the issue to resolve smart connect issue or not?