How to fix this
Turn off data roaming on your regular SIM
- iPhone: Settings > Mobile Data > tap your regular SIM (not Roamly) > turn off Data Roaming.
- Android: Settings > Network & Internet > SIMs > tap your regular SIM > turn off Roaming.
Set Roamly as your data SIM
- iPhone: Settings > Mobile Data > Mobile Data > select your Roamly eSIM.
- Android: Settings > Network & Internet > SIMs > set your Roamly eSIM as the data SIM.
Optionally: disable your regular SIM entirely
If you want to be extra safe, you can turn off your regular SIM while abroad:- iPhone: Settings > Mobile Data > tap your regular SIM > turn off Turn On This Line.
- Android: Settings > Network & Internet > SIMs > tap your regular SIM > toggle it off.
Prevention
Before travelling, always:- Turn off data roaming on your regular SIM.
- Set your Roamly eSIM as the active data source.
- Only enable your Roamly eSIM when you arrive at your destination.

