ummmm.....i see no smile in that icon....LOL
no idea. you can just look into the phone's notofiocation.....but somethingtells me that the phone is not yours and you do not want to ask the person who owns the phone.
unfortunately, we get this question almost on a daily basis. and the majority of these threads go unanswered. why you ask? well its because there are millions upon millions of apps out for android....each with their own notification icon......so you see unless it is something popular like tiktok or youtube, identifying an app just by its notification is like finding a needle in that haystack that everyone is talking about.
so unless you can look into the phone or get lucky and someone here recognizes it, i doubt you will find your answer.
never the less i wish you luck.