Twitter name squatting is getting widespread, lots of both personal names and brand names are registered by squatters. Annoying yes, but as long as the names aren’t used for malign tweets, there is a solution and it isn’t difficult to gain control over your name as long as you have proof (i.e. registered domain name, trademark, etc.)
Bots are scanning the Internet for new domain registrations, DNS changes and similar signs of web activity, and the domain name is registered as an account at Twitter. This is what happened to me when I revived an old domain by changing the DNS and setting up a blog.
The solution to this is to go to the Twitter help center and file a support ticket request. If your claim is legitimate, you’ll get access to your Twitter name within a couple of days, maybe more if the case is complicated.by