Sorry I have to tell you this dude:
If its saying that the current profile is not allowed on Xbox live - its not a treyarch thing. Either the profile you are using is banned , or the console you are using has been banned by Xbox. This is likely why the original owner sold it. TIP - do not buy second hand xbox's, especially not from a non-licensed Xbox dealer.
If the profile you are using is the original owners - try creating your own profile. Also, it would be a good idea to contact Xbox support and tell them exactly what the message says - this might help.
Here is how to contact Xbox support:
Can you play other games online? If you can't then it is definately your Xbox and/or account. It could be a deal where you account has a temp ban from inappropriate content or something else.
Does split screen ring a bell? Not really sure what this does for you
21 Kills by CHICHI8ANG8A(1)
Kill Confirmed On Nuketown 2025
1 16 CHICHI8ANG8ANG 3,200 311.18 21 7 21 0 2 16 CHICHI8ANG8A(1) 1,050 100.32 7 21 7 0