@StuppT Go to the support page and go through the installation guide.

  @DVair Who need "go read" smart useless replies like yours , Sir.
But in order to help people who may read this in the future I can say what was my problem and how it get resolved.
If you connect to the extender with web address or IP address or/and with Ethernet cable, doesn't matter,

you get page with one pass field - it means YOU DIDN'T RESET the unit.

All this online "instructions"  says "press the button" to reset. And I did it 100 times..

However my unit turned out to be has a little HOLE and it marked with hard to read "RESET"............
That was a little stupid problem which literally took life out of me.

HOW TO RESET.
Plug Extender in to the wall. Wait for solid light.
Take staple and put it in to the hole for 5 sec.
It will flash*(reboot) for another 5-10 sec than it stops - means reset complete.
After that when you go to the IP ot web address you get page with 2 FIELDS.
And  here you can create/confirm new pass.
And, admin page will OPEN.
 

You'll see your Router and when you click on it you will be able to create 2.4g and 5g connections one by one.
Be sure to give them different names. '1' and '2', or 'a' and 'b' or any other.

Something like that.
Anyway, RESET hole was my stupid problem.
And online "support",  AI chat - has NOTHING on that.

So much time wasted.

  @StuppT Sounds like you needed to read something if you can't tell the difference between the WPS button and the reset button.

  @DVair Oh boy.. Again smart a*s usless post wth attidute from you. Calm down already.

  @StuppT Just replying in the same tone that you had in your inital reply to my suggestion.