PhoneId.GetDeviceId returns a number, I see that my code convert it in HEX format, but this is not a problem, ok.
All my apps (hundreds of customers) are registered on my server with their IMEI and I use IMEI to identify cisomer, to send notification.
If suddenly the app can't read IMEI I must force the customer to register again with another code.
If there is no other solution I'll do it. But reading the link above, it doesn't look to me that it is no longer possible to read IMEI, it's enough you ask runtime permission and I'm doing it. Am I wrong ?