Transferring from private domain to wordpress free blog hosting??

Please be gentle, I’m self taught and not too savvy with the tech lingo.

I have two sites that I had hosted elsewhere but used wordpress for the layout thingy. (I’m not tech savvy – sorry).
The two sites were theveganista.net and the veganista.com
I stated with the .net and transferred it all over to the .com once I’d bought that domain. I didn’t end up doing what I wanted with the sites and now want to move the content to a wordpress.com free hosted blog type setup. But because I already have theveganista.com and .net, when I try this it says that the domain is reserved and I can’t do it.
Does that all make sense?

I’m all up to date with latest installations of software and wordpress. ??