I tried to adopt a Zentu on the 02/02, giving her the name "Harmonious". I was told that she's happy with the name, but I need to offer a shiny. So I bought a Shimmery Necklace, since if fits a Zentu look perfectly, but then was told that "Somebody already owns Harmonious" - presumably, "Name already taken". Unable to find out any way to check if a name exists before rollover, I had gone "Back", made a compromise of spellings and languages, tried again... and found that the necklace is gone. The replacement I had to offer as a result was nowhere near as matching the beast, but she ended up happy enough with the Gold Tiered Pearl.

Expected behaviour would be not taking an offering if the name is taken. And, of course, warning about it before going halfway through the adoption, somewhere near that text box. Or maybe something like "Is happy with the name, but feels it's not unique enough" and an ability to change the name without risking using a "Back" button. If names must be unique, give us a chance to check availability (and by "us" I mean newbies who are not too familiar with the ins and outs of the interface).

For future reference, you can use https://subeta.net/search.php to check if a name is already taken.

If a pet already exists with the name you want, check its profile too. If an account is inactive for a certain length of time, the username and the names of their pets will be available to use. There will be a notice on the profile if it is available, or due to clear at a later date.

But yeah, items shouldn't be lost in this kind of situation. I hope it is fixed!