Why would a narcissistic-sociopathic ex boyfriend still wish you a happy b-day?

I broke up with my ex boyfriend (a real narcissistic-sociopath) last Oct in very bad terms. I hated him at that moment. My family and I blocked him permanently and he still owes me over $1,200. I had to even have 3 psychological sessions because of him; he caused emotional damage.

I was furious that he had the nerves to text me a ''Happy Birthday'' 3 days ago on my Whatsapp (I blocked that number but he still managed to text me), just like that... as if nothing ever happened. Why?

Within me I'm thinking ''Wow, are you sick? Do you have any idea the harm you did? You hurt me, you hurt my mother, my grandma and you still owe me money you bastard. Seriously why do they still text you as if nothing happened?
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+1 y
I didn't respond at all. I blocked him once again. I was too furious too even reply.
Why would a narcissistic-sociopathic ex boyfriend still wish you a happy b-day?
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