Regarding Suim

I had searched some users having the particular t_code, after that I had deleted that t_code from the users going to object level and verified in the log and executed it in the log in, it is giving message" Not Authorised", so every thing is fine, however I am executing suim again to check the changes, it is giving the same result, why this confusing results, it has also given the names of the users that dont have that authorisation, I think i am doing some thing wrong, plz suggest.