Apparently they have. Looking it up, there are "multiple sources" that claim they have blocked his access to Twitter. There is a huge thing to keep his engagements short, so his message stays focused. But that can't happen for long if he's elected, so all of this careful control is just a HUGE illusion that he'll come ripping through, win or lose, in a few more days.
“Eternity is a terrible thought. I mean, where's it going to end?”
― Tom Stoppard, Rosencrantz and Guildenstern Are Dead
― Tom Stoppard, Rosencrantz and Guildenstern Are Dead