Trouble with gamer pic

is there a reason i cant change my gamer pic? I was temp banned on my main account, but im not sure if that has a cause in why i cant change it. I have my other account and i also cannot change the gamer picture even though i didnt get reported or anything
like that. I dont know why its doing this, and if anyone has a possible solution, lemme know. I am above the age of 18, so that also cant be why.

:)