GamerTag is taken, but searching for the profile yields no results. Why can't I have it?

So I'm trying to change my GT, but the two I'm deciding between say they are "reserved," or taken, but when I go to look for the user that seems to go by that GT, it doesn't show as existing. Why am I not able to change to these GamerTags, or how are they
reserved but not actually "used"?

Thanks

EDIT: This isn't actually the account I use; the one I'm trying to change is my "real" one and is going to cost me $9.99, so I really want to make sure the one I pick is going to remain cool, or whatever, for years to come.

:)

 

Bought Castle Crashers Remasterd on website, nowhere to be see on Xbox One

@SingCongButas25 Searching on the store yields no results.

 

Trying to claim unused Gamertag but says taken. (Support suggested making thread)

The name is taken. You searching for it might not yield a result because the search is strict about capitalization and spacing, however the system for assigning tags doesn't consider spacing (in other words, to the assigning system "gamertag", "GAMERTAG",
"Gamer Tag", and "G A M E R T A G" are all the same tag). For example, if you searched for "theoryofgame", you won't find a profile by that name - however, if you tried to change to "theoryofgame", the system will say it's taken (and it is... by me).

 

if the system says its taken then its taken its that simple

you have to be more creative with the spelling thats all

now also consideration is spaces does not make a gamertag different

so NGOC phi is the same as and will show that way but not in search

also when you search the website it only looks up xbox live not xbox pc etc etc