I have read on the TrueAchievements.com forum for NBA JAM: On Fire Edition that you can only accept the Terms and Conditions on an actual Xbox 360 console.
Some have even said that you might need to play a different EA title (i.e. Mass Effect 3 or SSX) and accept the Terms and Conditions from that title to get it working in NBA JAM: On Fire Edition. However, this is not an ideal workaround that EA would approve of.
On Xbox One via backward compatibility, the retrieval of Terms and Conditions times out and prevents players from playing in online matches.
This may only apply to players that have played NBA JAM: On Fire Edition before any recent changes to EA servers and/or EA's Terms and Conditions. New players might not be affected.
I hope this information helps the EA technicians in figuring out what is causing this problem.