Resetting Messages App

Having recently got an iPhone 5s, it is on a completely different number from what I originally had when setting-up Messages to receive my iMessages.
I've updated my Apple ID with my new number, but Messages itself still shows the old number, even after logging out and restarting numerous times.

Is it possible to completely reset Messages and put my Apple ID info in again?

Any help would be much appreciated.

I've only seen this happen where a number has been ported in when switching phones.

Settings - iMessage
Turn iMessage off

Settings - Phone
Ensure 'My Number' is correct and has your current number.

Reboot the phone.

Settings - iMessage
Turn iMessage on
Let it authenticate

Check Settings - iMessage - Send & Receive
Make sure your new number and any required email addresses are set correctly

Fantastic! Worked a dream. For some my Mac still received messages to my old number, but that problem has been solved completely due to the instructions above.

Thank you very much!

good stuff