My gamer tag was changed what happened?

You would have been given a forced name change because your gamertag violated the code of conduct. You can change it to something of your choosing, but you will have to pay for it. You would need to post here for an official response from the enforcement
team on why it was changed -
forums.xbox.com/.../41.aspx

the free gamer tag change was only allowed when your gamer tag change was forced. People abused this by reporting gamer tags that people wanted to change so once a force change was made they then changed it again to what they wanted for free. Because
of that abuse of the system all game tag changes now cost even if a force change has happened.

Hi there what has probably happens is the community has reported your Gamer tag for what ever reason and they have changed it sorry

Hi MOBZ SHOOTER,

Thanks for your post. I understand you are experiencing an issue with your Gamer Tag not changing to what you intended to select. Do you mind posting what Gamer Tag you had before, what you wanted to change it to, and what Gamer Tag it actually changed to?

For more information regarding GamerTag changes check out:
Manage Gamer Tag.

I hope this helps.

I'm going to assume that what is going on is that you were issued a forced gamer tag change since the gamer tag may be deemed offensive. A forced gamer tag change can result in not being able to post on the forums until that gamer tag is changed.