Hello ​@Mags May W-s 

This does sound quite odd. So your friends and family contact you, but a different number shows on your handset when the call or text comes through?

Yes. I am abroad and I have asked a forum. Others using the 3 network are also facing similar issues. No idea how to fix it  

Probably because they are calling you via an app like what’s app, messenger or something similar rather than calling using the mobile voice network. 

Hi ​@Mags May W-s 

​@MZone raises a good point, are you receiving standard network calls and having this issue or is it a third party app like Messenger/WhatsApp?

Tom