MMS app notification LED problem !

Hi guys ! I'm having a problem with MMS app. When I receive a Message , LED doesn't notify me.. First I thougt that it conflicts with Facebook Messenger app cause they share the same notification color category , but after I've freezed it I still got no LED notification for SMS. The LED works perfect with any other app.

MMS app it's already set as default messaging app and has LED notification permission. Does anyone has this problem too ? I'm using xiaomi.eu 6.7.14

Thanks !