IPhone fifteen versions are activated with an eSIM and do not assist a physical SIM. Usage of an eSIM requires a carrier that supports eSIM in addition to a wireless service program (which can include things like limitations on switching support suppliers and roaming, even just after agreement expiration). See https://holdencukap.goabroadblog.com/29068594/phone-case-iphone-15-pro-fundamentals-explained