You may do so via Internet Banking (IB) or at your nearest branch.
Nothing, the SMS banking service is attached to your phone number and not to your mobile phone.
You need to visit your nearest branch for the necessary amendments.
Should such a situation occur, you need to contact your mobile operator immediately to block the sim card. You should also inform the Bank by calling 202 6060 or visit your nearest branch in order to block services such as Refill, SMS banking and Juice.