[Wordpress issuses] thiagoincsf on "Site already exist"

I made a blog a few mounths ago, but I deleted it for personal motivation. But now, I want to reuse it. So, when I'm creating a new blog, I can't putting the same name of the site of that blog.
I changed my username today (9th april), to try a solution for my problem, but I failed.
So I'm asking to you, I want to use that name (thiagoinuk) to my new/old blog, to use wordpress as my personal travel blog.
Please, could you help me?

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