I haven't been on WordPress for a while and decided to make a new blog, as well as delete my old one. I changed my username too, and I chose the option to get a matching URL and delete my old website (= something along the lines of "Yes, create a URL matching my username and delete my old one" when I was asked whether I wanted a matching URL).
Because I had deleted my old blog already, the option I chose didn't really affect the older one (since it didn't have to delete the old blog). So I went to see my 'new' blog (which would be qwaszillio.wordpress.com) and it didn't exist, so I thought it might've been because the option I chose meant that it would replace the older blog, not create a new one whilst deleting the older one.
(I checked to see if the new blog had been created but it wasn't in the list.)
I went to create the blog and typed in the URL I wanted and it said the site already existed. Then I went to check if it had actually been created and my list hadn't been updated (see first picture), and it said it was deleted (I think this is because my older blog was deleted).
So... help? Are you actually able to create a blog using a deleted name? (Might be one cause of the problem, I guess.)