This is a normal phenomenon. The watch system optimizes the strategy of message reminder. Considering that there are many message notifications in normal use, it will frequently touch the bright screen. On the one hand, it will have a certain impact on power consumption, on the other hand, it is also an excessive disturbance. Therefore, the strategy of message notification and reminder is updated. When the message comes, it only vibrates and does not actively light up the screen. The control right of viewing is in itself.
You can set this mode by yourself on Mi Fitness app: App notifications > Wake screen > turn on.
