On Bedrock They Are the Same Name
Your Minecraft name on Bedrock is your Xbox gamertag. Changing one changes the other, because there is only one name and Xbox owns it.
That is why it cannot be changed from inside Minecraft and why we cannot change it for you. It is done through Microsoft, on your Xbox account.
Java Is a Different Game
Java Edition has its own username with no Xbox account behind it, which is why a Java name is never found here and why a Java server address will not work in Bedrock.
If a friend sends you an address that works for them on a PC and simply refuses to connect for you, this is usually the reason.
Your LecternMC Username Is a Third Name
The name on your account here is ours rather than Xbox's. It is what appears on skins you upload and servers you list, and it can be changed once every 14 days from Settings.
Changing it frees the old name for somebody else and changes your profile link. Transfers are searched by these usernames rather than by gamertags, so a friend receiving a listing has to be found by the name on their account here.
Renaming Does Not Move Your Profile
Renaming does not give you a second profile. A profile belongs to the Xbox account rather than to the name on it, so the page stays the same page, your new name becomes the current one, and the name you dropped joins your name history underneath it.
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