I got this unit from Carmount (Clutch-X One) on Amazon. It is just a magnetic phone mount, and it works well. You mount it to a smooth surface using the dial to turn on the suction.
https://www.amazon.com/dp/B0FB9BYGSJ?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1
I had the same problem for over a month. I took my car to the service center. They applied a number of recalls - ARC5, ASA3, WRS6. It took care of the problem with the app not syncing with the car.
I have had my Macan 4 for about 6 months. It was working great. About two weeks ago (on 4/18), the MyPorsche App stopped getting any current data from the vehicle. The battery levels, vehicle location etc is stuck at the value on 4/18. I cannot start pre-climate and I cannot see the battery...