Device requiring 2.4 ghz band and set up through smartphone

OK.  So, the Rotomatic app sees the Rotomatic WiFi, you connect, and the screen on the Rotomatic says "Phone synced to Rotomatic".  (Page 20)  You enter the Orbi SSID and password on the Rotomatic app.  Is this one of those apps that does not show which characters you have entered?  (i.e. puts dots or asterisks on the screen as you type)   The Rotomatic screen then shows "Connecting Rotomatic to Internet" (Page 21), but it never says "I am connected to Internet now."

My sense is this issue belongs to Rotomatic.  The Orbi broadcasts a 2.4G signal. The Rotomatic looks for a 2.4G signal.  You have a good WiFi signal where the Rotomatic is located. (It is not blocked behind metal appliances or something?)  You entered the SSID and password with the correct upper/lower case.  And, it never connects.

I had several episodes of frustration connecting cameras to WiFi because my stubby fingers would enter the wrong letters and their app didn't show what I had entered.  A LOT of gnashing of teeth.  Page 45 of the manual suggests reinstalling the Rotomatic app.  I doubt that would help, but that's what they suggest.

I think you can fiddle with the Orbi 5G signal until hell freezes over and it won't do anything to solve the problem.  We had a community user with a Whirlpool microwave he could not get connected for six months until finally the Whirlpool engineers made it work.