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This tag I've been trying to change my name to says 'This tag doesnt exist on xbox live' < Not precisely - but you catch my drift.

Usually if you invite a tag which is glitched to private chat, it will take you to the profile.

This tag still says 'This gamertag doesnt exist on Xbox Live' or something along them lines when you try and invite it to private chat - this tag didnt appear but showed the message mentioned earlier in the sentence.

Does this mean this gt is being reset or something? Idk..

No, I will not tell you the tag.

I'm assuming it could be a deleted tag?

I know tags such as God, Jesus, Predator, etc. are deleted tags and when you try to add, chat, or message them it says the Gamertag doesn't exist but you can't claim it either.

If that's not it then idk man.

This could be because it is an account on another microsoft program, I talked to an employee about this before thats what they told me.

Most likely just a deleted tag.

Still may be a glitched tag. If not it's deleted or spaced.