How can i change car registration ?

Friends, i am a P.R.O. (Mandup) but it is my first time doing this kind of Mandup work. i made a mistake and i have too much problem. my manager is pakistani and he bring his relative person from pakistan for teach his son. my manager buy a car for him and made registration by name of that teacher own. after some month teacher quarrel(fight) with my manager then manager told me that cancel his visa and i did but by mistake all cancelation paper and passport i gave him and he took all to pakistan and i dont have any document of him. now registration of car is expired. so friend can you tell me that is there any way to change registration name to my company. my manager dont know about this matter. my job in danger. plz help me