Purchased armor set not showing up in collections

I just bought a new armor set and equipped the pieces i liked in my outfit, then deleted the other ones to save inventory space. I now wanted one of the pieces and went to look for the set in my collections but it wasn't there and there's no option to purchase the ability to unlock it with other characters like I've done before. What's going on, what do i do and how do i contact SWTOR support for help? Thanks.