How can I change the phone plan on my iPhone 13?
Need to switch out my sims card so I have a new plan
[Re-Titled by Moderator]
iPhone 13, iOS 18
By "new plan", I assume that you mean that you want to change carriers.
Contact your current carrier to make sure that they have unlocked the phone
Then, contact the new carrier that you want to use and ask them set up your phone for service.