It is advisable to do it yourself. TATA Sky customer care are trained professionals however in order to change any account pack, you need to login to your account with your credentials which you have. TATA Sky do not keep access to our customer's personal information. However, if you have any doubts or questions you can call the customer care at 1800 208 6633 which is a toll-free number and is available 24/7. If you must get it done from the agent itself, you can check with them to see what they can do.