Why did he text me out of nowhere?

ChelseyLately
My ex-best friend/ex-boyfriend texted me wishing me a happy birthday after 3 weeks of not talking to me, & being EXTREMELY mean to me the last time we talked 3 weeks ago. He told me to lose his number & that there was no need to thank him for teaching me a lesson about how guys really are, now he wants to text me?
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+1 y
He also did not come say bye to me before I moved 14 hours away, & is coming to visit where I live (he's from here) in 2 weeks before he deploys.
Why did he text me out of nowhere?
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