Why did this guy purposely liked than unliked my post that a month later he liked my post again?

I posted this post on my Instagram in February when it first came and He liked that post I didn’t think much of it because he is a friend of mine and he is following me and he is gonna like it bc it prob showed up in his feed anyways a month later he came back to the same exact post and unliked and liked it again bc I am assuming in order for me to get a new notification saying he liked the post he liked in the past, he would’ve had to unlike than like it again? Also it is a month old it wouldn’t show up in his feed unless if it’s new which means he went on my profile and did this? Anyone know the explanation or am I just overreacting?
Why did this guy purposely liked than unliked my post that a month later he liked my post again?
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