Ultimate Team disappeared on Xbox

Hi my son's ultimate team just disappeared last night, after he played a game.  I have tried the online chat but they have not been very helpful and just said well if it has gone it has gone and all I can try to do is ask on here for help.  Has anyone else had this? He said he got a message (after playing a game) on his screen saying "88+ icon player pick completed" but he didn't do anything, this message just came up then his team disappeared.  He has used birthday, Christmas and pocket money to buy players and packs and it has all just gone in a blink of an eye. I am not great on these things so if anyone can suggest anything we can try I would be very grateful. We are based in the UK. Thank you