Facebook reaction is only available for new Facebook profiles (2-3 year old only).
As you all know that Facebook released new Facebook reaction for posts,photos etc. But maybe some people not got this feature.
This feature is available in Facebook app,Desktop browser, and also available on mobile browser but only 2-3 old profiles. Dont know why its not available to old profiles.
I personally tested this feature in my friend’s newly created profile. But its not available on my profile.
First i thought that maybe i need to reinstall Facebook app in my mobile so i reinstall Facebook app but still same problem. But when i logged into my friend’s account which is only 1 year old then i see that it will Facebook reaction and icons are also changed in notification (i logged in, in mobile browser).
So i get to know that maybe this feature is currently available for new users only and maybe soon available to old profiles too.

But if you have morethan 6 year old profile and got this Facebook reaction then comment below.
And i m still testing and will post solution if i got this feature on my profile too.