Disable IMessage When Switching From IPhone to Android
When you jump from one platform to another, there is always a slight hiccup. For example, if you’re switching to Android from an iPhone , be sure to turn off iMessage.
Some phones will prompt you to do this when you switch, but otherwise you might notice that you are not receiving messages from iPhone users on your new Android device (or other non-Apple device). Chances are, you are still logged in somewhere: perhaps on your Macbook or iPad. To fix this problem, simply disconnect your phone from the iMessage app and then disconnect it. Or follow the link below to help you unregister your iMessage number entirely.
Unregister iMessage | Apple