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Out of curiosity, why would you tell someone that you noticed they unfollowed you?

Why not ? and I thanked you for the time you did follow me , that is not bad! Or is it ?
I do think it appropriate and yes the notifications tell everything.
So chill it’s only Monday it’s fine don’t follow whatever !

I've not had anyone respond as you have to an "unfollow" before! Personally, I would not acknowledge anyone who unfollowed me. We have a difference of opinion, nothing wrong with that. All good!