@Tiamaria
No need for a new sim at all.
But you will need to call O2 to switch your data bolt on to standard data.
Also, deregister your number from iMessage.
https://selfsolve.apple.com/deregister-imessage/
I have no affiliation whatsoever with O2 or any subsidiary companies. Comments posted are entirely of my own opinion. This is not Customer Service so we are unable to help with account specific issues.
Please select the post that helped you best and mark as the solution. This helps other members in resolving their issues faster. Thank you.
