I just went through something similar to this, but it wasn't a butt dial that started it, but an "hope you are doing well" email.
Fast forward 5 months later (a really great, fun 5 months later) and he pulls the vanishing act once again....Now I have to go through the pain again.
My advice-delete his # and any other info you have on him, and save yourself the pain I'm going through right now....
Will I ever ****ing learn?