Cant share car designs or find other peoples!! HELP!!

I’ve been playing Forza 5 for a couple of days now and it’s never let me share my Designs on the community on Forza 5,at first i thought it was a general issue but then found out it works perfectly find on my brothers. I don’t if its because my name is too long because on forza it says my gamertag is JumPinGBanANa9.It actually is JumPinGBanANa94. idon’t know if thats the problem please look into this Turn10. Thanks.

JamesStone