user creation hook

Hi
I’m trying to run function when user register.
my function create a post for every user. (I need post for every in addition to the profile page)

I use ‘um_user_register’ hook.
The function is running when the user is created from the wordpress admin but not when a user is registering from the register page, (the page that was created by the plugin)

Is there anther hook I should use?

thanks
Asaf