Multiple WordPress Accounts

So I had a regular wordpress.com site, then decided to buy a domain and get hosted. Once I installed wordpress I was asked to create a new account so I did and moved my blog there. Now, whenever I comment on people’s posts, it automatically links them to my old wordpress.com blog, even if I’m not logged in.. I went to delete my account but I couldn’t. I made a post linking them to my new site, but it’s just a hassle. It’s like I’m permanently stuck to my old blog.

Is there any suggestions on what I can do to ensure I’m logged in to my actual blog and link them back to my domain instead?