The exact cause of the problems encountered by the users is unclear. According to reports, this affects both the pixels 3a and 3a XL, but nothing indicates what triggers the problem. This does not seem to be limited to one carrier. A user attempted to reboot his phone in safe mode to ensure that no third party application was involved and that she was still undergoing a shutdown, suggesting that no one else was involved. it may be a problem with the Google software.
It's far from the first time that Google's Pixel range is suffering from a major problem. The company's original Pixel phones were plagued by microphone issues that ultimately led to a trial of the device owners. Last year, shortly after the launch of Pixel 3, users reported that the phone did not record their photos. But at least in these cases, the phones did not stop without warning.