Your friend could not attend the concert.
That is unfortunate.
It does not mean everyone behind you has agreed to watch your friend attend through a floating rectangle.
A brief FaceTime call during one favourite song is understandable.
Holding your phone above your head for the entire show while shouting, “CAN YOU HEAR IT?” every thirty seconds is not.
They cannot hear it.
They can hear distortion, screaming, wind noise, and your thumb scraping against the microphone.
Meanwhile, the people behind you are now watching the concert through the back of a phone displaying someone sitting on a couch in another city.
Your friend is not at the show.
You are barely at the show.
And the rest of the section has somehow become unpaid background talent in a video call nobody asked to join.
Send them a clip later.
Tell them about it tomorrow.
Buy them a ticket next time.
Do not turn the entire audience into supporting cast for a two-hour FaceTime call.
Official Warning
If the person on your screen has a better view of your face than you have of the stage, something has gone wrong.