Problem principal xbox

It may be that the Home setting has been maxed out on your account. You should call phone support to request a reset. Please click this link to get the number for your region http://support.xbox.com/contact-us?isChatCallAvailable=false

1) Oh, maybe that's the problem.

2) It's the same Xbox and I checked the two accounts and both says Xbox Home (Xbox Principal).

Thanks for answer my questions.

You only have to put in the console B or C the account A as principal and so that the other one that was left without the account A as principal can take advantage of the resources only must have the session initiated of the account A.
Besides that there will be no problems when playing together between A and B but if they want to play A and C then they will not be able to do it since C does not have the account of A as principal.

Olá N3WSUNSH1N3,

Você pode ter apenas um Xbox One principal ao mesmo tempo.

Se você atingiu o valor máximo do Xbox One Principal / Principal (esse limite é 5 em um ano), será necessário aguardar até o próximo ano para definir outro Xbox como Principal / Principal.

[Original text]

Hello N3WSUNSH1N3,

You can only have one Main Xbox One at the same time.

If you have reached the max amount of Home/Main Xbox One (that limit is 5 in a year) you will need to wait until the next year to set another Xbox as Home/Main.

There's the problem friend, sharing accounts with friends is not a good practice, this out of terms of use and your account can be banned, especially if your friends' xbox and have on different networks, one day will give you trouble. Try resetting your
password and resetting your xbox's configurations by soft reset, to you keep your games in console and only clean the your user data