Xiaomi sent out the January update to the Android One Mi A2 earlier this week, and there have now been multiple reports of bricked devices after installing the OTA. Unpolished updates may be becoming a theme of Xiaomi's Android One phones.
https://www.notebookcheck.net/Mi-A2-users-have-reported-multiple-cases-of-bricked-phones-after-installing-the-January-update.400346.0.html