Dear bleeepbloop,
We are sorry to learn your phone has been stolen.
You don't have to cancel your contract, but simply order a new Sim card with the same number.
As soon as we get your mobile number and personal details by private message, we will send you a new Sim card by mail. Alternatively, you can go to a Swisscom Shop to get your new Sim card if it is more convenient for you.
Furthermore, we remind you that our customer service is available for you 24/7 on the free number 0800 800 800.
Kind regards,