Hanging on the hel(p) line

Searched on the app for the flight I wanted (an app whose interface seems to change weekly) double checked my times and dates... just before I go to payment I received a phone call... ok back to the app: times out.. but offers a helpful link to repeat my search
Great, booked, paid for then get the email: it's not for the Friday I wanted, it's for the very next friday.
Now, I happen to have a degree in Computer science, so I can speculate with some certainty that the coders who put this 'repeat your search' link in perhaps, did not complete a rigorous test regime, especially if the coders are underpaid and harried as all other OneStar staff.
I finally got to speak to someone, they wanted $139 to book me on the flight I originally searched for. I argued with them... more waiting, then finally a "just pay the difference to the ticket you want: $60"
She was claiming the flight I wanted was $171.
Exasperated, I hung up. Went online and sure enough the flight I wanted was there: $139
She lied to me.
I repeated tried to speak with a supervisor but 'none were available '

I immediately delegated their deceptive app.

My advice if you are ever on the phone to them is never hang up.
I suspect they can't end a call, so just stay there until you get satisfaction.
Perhaps with a big sheet of bubble wrap.