hmmmm no idea.
so we get this kind of question every day. with millions of apps (and even websites) that have notification icons, there is just to many to be able to recognize just from seeing what the icon looks like. you might get lucky and someone here might be able to recognize it, but most of these threads go unanswered.
the only tru way of knowing is to go into the phone's settings and look for the notification. but most of the time, the phone is inaccessible for one reason or the other.