If you're traveling with an eSIM and your carrier is billing you for roaming charges, it’s likely because your primary SIM is still active and being used for calls, texts, or data. Here are a couple of options to avoid these charges:
Disable Your Primary SIM: You can turn off your primary SIM until you return home. This will prevent any charges, but you won't be able to make or receive calls or texts on your regular phone number. If you have an iPhone, you can still use iMessage and FaceTime if they're linked to your Apple ID.
Switch to Pay-Per-Use Fees: Alternatively, you can ask your carrier to cancel any travel plan they have placed you on, which typically charges a daily rate. This way, you'll only pay for individual calls and texts, but again, you’ll need to keep your primary SIM active.