@zanakakil77: If you have access to a home computer, then you can change the phone number that is registered to the 2-step verification process on your Samsung account from here. For a useful guide on how to proceed, please take a look at the link below, and scroll down the page until you find the 'PC' steps.
When you set up 2-step verification, you should also have received a confirmation email containing backup codes, that you can use in the event that you don't access to a mobile phone. With this in mind, please check your email inbox for the relevant email, and explore the contents to find the code(s) you need.
