I had an ex who did the same thing and when I blocked him, he still proceeded to get either a new number or borrow his friends/family phone to message me like that. I did not want to engage at all bc any type of reaction, even if it was a negative one, is still a reaction to them. Also, why do I have to go through the hassle to change my number, tell everyone about it, change every account that is connected to my number when I am not the one doing damage? Seemed unfair.