How do I remove an addon domain?

[SwiftyUK]

I setup an addon domain and it looks like it's taken control as my main domain because when I try and delete it, I get told that I cannot delete my main domain, which it shouldn't be!

How do I delete this and get my main domain back in the "Manage another account" list?

p.s. I only have access to cPanel.

[chirpy]

Please don't cross-post on the forums.