Hi, long time the "aries" don't have custom rom based android 7 or 8, now, it comming from some dev and official build by mokee, i already try this rom, and this is most stable rom.
Based AOSP
https://forum.xda-developers.com/mi-2/general/rom-android-8-0-7-1-xiaomi-mi-2-2c-2s-t3707371
Mokee...