Why does my friends with benefits not take the hint I don't want to keep sending nudes anymore?

I decided I had enough settling for this one particular causual relationship I started with a guy in 2017 when I was traveling the states. I ignored in October but I could see that he was reaching out to me through email pretending to know how I was and what I was up to I fell for it and again he's asking for nudes. Put of the 4 years I've known him all he gave me was severe mixed singles saying he wanted something more then he would change his mind and asking if I wanted to life together...
Why does my friends with benefits not take the hint I don't want to keep sending nudes anymore?
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