I have had the same phone number for about the last 10 years and for some reason today a new one is showing up under my Apple ID as being able to send IMessages.
I am trying to de register this number but the online help is only able to send a text with a code to the new unknown number. Any ideas how to get this sorted?
Where is the SIM with the Old Number, If it is not with you or you have given it back to the Carrier Service Provider, Then don't bother about it? Then de-registeration is not required and also not possible.
If you have it with you and want to use it with an Android device then put the SIM on any Phone (Apple or Android) and follow the GIF
Insert the same SIM into an Android or an iPhone. You may deregister iMessage online
Watch the GIF below. Here I have used another iPhone for the demo but for you, it may your choice. Android or iPhone device.
Where is the SIM with the Old Number, If it is not with you or you have given it back to the Carrier Service Provider, Then don't bother about it? Then de-registeration is not required and also not possible.
If you have it with you and want to use it with an Android device then put the SIM on any Phone (Apple or Android) and follow the GIF
Insert the same SIM into an Android or an iPhone. You may deregister iMessage online
Watch the GIF below. Here I have used another iPhone for the demo but for you, it may your choice. Android or iPhone device.
Help de registering a phone number
