It's been a long time since I've done it, but I seem to remember that purchasing the extra slot put something in your /claim window. My memory may be way off, but it's worth a check.
I purchased from the login screen, not a character. There was no virtual item to click. There's nothing in my bags and nothing in /claim.
Then you need to use the /petition command, which will bring up a browser window so that you can submit customer service request.
Yeah, that's weird...I've done that myself, bought a character slot from the character select screen, but I've almost always gone immediately into creating a character right then and there. :-/ Did your perhaps greyed-out Create Character (1st level or 95th level) bar go green? At that point, I'd character create immediately, but I can see how other folks might want to hang onto it for a bit until they could decide where and how to "spend" it. :-/ Uwk
This has happened a few times to customers purchasing from the character select screen. If you browse these forums you'll see a few similar issues. Sometimes CSR's respond here which is why I posted here. I have locked characters because I have cancelled my sub. I used leftover DBG cash to purchase a character slot so I could access some of my locked characters to give stuff away. I've got two I need unlocked but since none were unlocked after the first purchase I didn't buy more until I can reach customer service. I should have logged in and bought directly from a character so I'd have the item, but I didn't. I suspect that the reason this happened is actually because it "unlocked" a character slot that cannot really be unlocked. I have two additional toons on TLE servers which require a subscription.
I assume they still answer petitions, particularly when it involves a marketplace purchase, but I could be wrong.
Character slot unlocks can be tricky. It will unlock the most recently played character. If that happens to be a character on a premium server, then you still would only have access to it once you have access to that server. You might be better off just buying a krono, getting everything off the toons you don't want, and then make sure the toons you want are the most recent to log in before the krono runs out.