I am confused.
You talk of signing up for a blog. You don't quote its URL, and then attach a message concerned with this the "Free Support" forum when you raise a query about your blog.
Nabble's "Free Support" sub-forum of the "Nabble Support" forum, has nothing to do with your blog which will have its own URL and own login.
When you signed up for your blog you will have been sent a confirmation email. You need to click on the link provided in that email to activate your blog.
If you have not had the email, make sure this has not been sent to your mail service's spam folder.
Once activated, you will find a login link at your blog's URL.
Volunteer Helper - but recommending that users move off the platform!
Once the admin for GregHelp now deleted.