So due to my individual needs, I use an iPad and FaceTime instead of phone calls.
But when I’ve tried to register to use app to check my usage etc it request my telephone number of the SIM card, so it can send me an sms code to register.
Smarty saw this problem and had send via email option. I D mobile doesn’t so it’s next to useless as can’t register so going to have to cancel subscription with you!