Using EL expression for organization

Hi,

I have to pass a default value for organization at run time when creating user. so to achieve this i have used EL expression #{oimcontext.currentUser['Organization Name']} and specified this in value field in ui customization.  The value is getting displayed with logged in users organization when we click on create account.  However it is throwing error mandatory fields are required though the value is present. when We reselct the organization value then the error is not coming.  Could you please suggest is there anything I am missing.