Subaru Outback 2018 Touring: found the hatch door opened on its own twice in 3 weeks. It’s parked so nothing happened except it drained battery and a lasting beeping noise when driving it. Called the dealer service and was told it might be an electrical problem. It’s new with only 5000 miles and just first service at the dealership.
Allow the dealership to diagnose whether there is indeed an electrical problem with your fully-warrantied vehicle.
Make sure that the key/key fob isn’t put into a pocket or purse in such a way that the appropriate button for hatch opening on that key/key fob is accidentally pressed.
Almost all cases of mysterious openings of sunroofs, windows, and hatches is the result of the key/key fob’s button being pressed inadvertently.