I hered that you have to complete the journal but that didnt work

Beat all Worlds.

 

Then beat the story again and Save your Clear Data.

Also you really can't complete the journal without beating lingering will so don't wait for a Mickey symbol on the characters

To be safe, clear all worlds, beat the game and save clear data.

so play it onther time

Beat the final boss of the game. Unlike KH2, you'll be able to save with unlocked content after ending the game. You'll receive a note that a powerful new enemy is hiding in a world, Disney Castle.

No, do not play it all over again. Beat all worlds and go defeat Xemnas once more.

so complete the jourmal

Actually you can't complete the journal without fighting him so, just beat Xemnas and then he'll be unlocked!

i got to the fight and he owned me thanks for the help