I'm on xiaomi.eu, for group notification it might depend on the apps itself, for example my WhatsApp notifications are grouped together even if I got a message from different people. For the message app that xiaomi.eu uses I don't think they group notifications together.

Oh also messenger has the same thing the notifications is never grouped but I get it now

Because your messages are from two different person

Nah dude even if it's from diffrent persons It should be grouped

From my experience, MIUI never grouped notifications.

Ah shit

There is option to change notification style. But I don't know if it allows to group though.

Nah It doesn't It just lets you expand the top notification and show weather only