Twitter DM ing trouble?

[Stasia]

So this kid DM Ed me and it wont let me DM him back. It says "Your message could not be sent" He doesn't follow me but if he dm's me first and I'm trying to respond, it shouldn't matter. I'm not blocked and I can DM other people. I've gone to twitter support nothing helps. I logged in on my friends phone and it didn't work. I logged off and on. I opened a new page and nothing is helping):

[Neil]

This is not a Computer Networking question.