Hi @NaomiBuff,
Welcome to the EE Community
I am sorry to hear your replacement SIM has not arrived. As it has been several weeks it would suggest it has been lost in the post unfortunately.
Was it a replacement for a lost SIM? If so you can order a new replacement by giving us a call or by visiting an EE store with photo-ID.
If you still have the current SIM available, you can order a new one via your online account including the option of downloading an eSIM if your phone is compatible, our help page has instructions. Or you can also also call or pick one up in an EE store.
Alex
