Deletion of Parameter value from user master maintanance

Hi all,

I am trying to delte the parameter value using the below ABAP attribute. but i am able to add some value and not able to delete from any user ID. kindly let me know whether i have to make any changes to the attribute and its value.

Parameter1 - if i give CRM_UI_Profile, its getting added. i am not able to remove the value.

Regards,

Dileep