Have you noticed that when you check your notices, when someone 'likes' your post, it appears twice? It doesn't happen all the time.

There are a couple of reasons some could show this way.
You asked a question they liked.  You answered on the same question and they liked your response.  They liked all the responses you had on a question.  This would show a person liking more than just once on a single question. This post was edited by Merlin at April 24, 2020 7:32 PM MDT

No. I have noticed that there is one notification for a like and another for a reply. If you get multiple like notifications, it could be that the person liked two different comments that you made.

No, I think you’re just seeing someone like multiple posts in the same question thread. 

  Nope.  What the heck are you even blithering about?

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  Nope.  What the heck are you even blithering about?

~

Perhaps.... just perhaps.... 
It is because you are special to many and so likeable!

Big Smiles!!