What is the "manic behavior?" What did this "authorized representative" tell you to do to stop the "manic behavior?"
Sometimes the screen is not sensitive at all, sometimes it is oversensitive. Sometimes the phone starts typing by itself, opening websites, other apps, selects an email adres, starts typing vvvyyyvyvy in the mail, calls someone shortly, drops the call, recalls someone else, opens another app, .... I thought it might have something to do with the bluetooth with the i-watch because it didn't happen some time ago when i left the i-watch home... Today i'v put on the watch again, and there it was.
What is this "sudden instability?" What did this "authorized representative" tell you to do to stop the "sudden instability?"
I didn't go to the store with the problem yet because i thought it would fix itself by software upgrades or so ... and i don't want to hand over my phone for couple of days to a technician - i really need it - and getting into a hassle about who's fault it is or not is...
It is just strange i got an email now from this store to buy a new phone while having all this trouble with my current 6plus phone. it s probably a coincidence but an unfortunate one not?
Did you attempt to contact Apple directly?
No that i didn't do. Reading your question it might be the solution. I know they have a friendly all hands on service desk... I'll try tomorrow. Let's find out if that works. If it works I'll be happy to post the news :-)