Hi I have transferred my old number to a new phone and SIM card but it is showing the Sim original number and not my transferred number, how can I change it

Settings, Messages, Turn off iMessage

Settings, Face Time, Turn off Face Time

Restart the phone.

Settings, Messages, Turn on iMessage, SMS, MMS

Settings, Face Time, Turn on Face Time

There are two ways to do this:

1. On your iPhone, go to Settings > Messages > Send & Receive. Select your Apple ID at the bottom of the screen and tap Sign Out. ... 
2. If the phone number that you want to remove belongs to an iPhone that you can't access, change your Apple ID password.

Add or remove your phone number in Messages or FaceTime