What if I change my mobile phone?

You can activate the e-SIM in your new device,
but only if you remove the cellular data from the previous device,
and use the same (QR) Code that you have in your email, or you can call 156 for assistance,

and it depends on some IOS devices.

and also you need to check the if your device supports e-SIM.
and if it is not allowed The e-SIM must be changed.