phone number not registering to my iphone

i recently swapped mobile providers (three -> O2) and used a PAC number to ensure i kept my original mobile number with the new sim card

i inserted my new sim when it came in and it had a temporary number at first but then changed to my original number after a day or two - at first my phone still registered the sim with the temporary number but now it registers my sim with my original number but i can't receive/call non-iphone users

anyone have tips or advice from previous experience as this is getting pretty frustrating