I feel you..
Just so we are crystal clear, the problem I am talking about is random disconnects of Carplay/AA.
The randomicity is what drove us crazy here, it was sometimes happening only a few times in the first 10min of the ride and then stabilize, it could happen later in the ride, it sometimes did not happen at all (we had a theory here that warm weather improves the connectivity, which was quickly proven wrong). It sometimes happened when going over a bump but not all bumps and many times on smooth sections. Of course I ruled out cables (oh so many cables), phone type, phone SW, car's SW and phone malfunction (if I hear one more time the 'lint in phone socket' advise I'll hurt someone).
Given its finicky nature the problem is not always easy to reconstruct at will, and also does not leave traces in the log files.
So if that describes your problem, please tell your dealer that in Israel we have a group of i5 owners created specifically for the purpose of convincing our local dealer (Colmobil Corp, Hyundai official importer in Israel) of this problem. Colmobil did step up immediately and fully acknowledged the problem. I personally know of 4 cases where replacing the USB port (and internal cable, it's one part) immediately and decisively solved the disconnects. There are probably more successful cases that did not report back yet, plus some are still awaiting the part to arrive. BTW ask yourself why such a simple generic spare part is in such a shortage WW, maybe because many dealerships are ordering it?..
Worth mentioning it is a cheep part that is relatively easy to replace - they should replace it even if as a gesture, just to keep you happy.
Bottom line - don't take no for an answer.
Good luck!