I am unable to activate iMessage on my iPhone

Re: "iMessage: when i try to select my phone number on IMessage i get a notfication ‘

"an error occurred during activation’’ i couldn’t fix it.

i did everything mentioned on the websites. Need help please".

If you are new to Messages:

How to: Set up Messages on iPhone - Apple Support

or

What to do: If you can’t turn on or sign in to iMessage or FaceTime - Apple Support

or:

If you can't send or receive messages on your iPhone or iPad - Apple Support

Also:

How to: Add or remove your phone number in Messages or FaceTime - Apple Support

If needed:

Apple Messages Support website (info. / support / contact)

Messages for iPhone, iPad, Apple Watch, and Mac - Official Apple Support

Wondering what happens when you try, which iOS version is installed on your iPhone, whether Messages has been working ok before, and whether or not you get an error message that would help troubleshoot.

You may need to check your iPhone is updated the latest compatible iOS version:

You can check if an update is waiting for you to install:

See: Settings > General > Software Update

If your iPhone is already updated to the latest compatible version, you could try re-starting it (re-establishes connections, deletes temporary files, and much more): See how to: Restart your iPhone - Apple Support

Please I can’t be able to send message on my iPhone iMessage