Update required

CallumB I have just asked my good friend Señor Google. He in turn asked his good friend Señor Apple. I'm not sure if you have seen and tried the following (my apologies if you already have without success): 

1. Make sure that your device is connected to Wi-Fi or a cellular network.
2. Tap Settings > General > About.
3. Follow the onscreen instructions to install your carrier update.

If you set up a new eSIM or insert a new SIM card into your iPhone or iPad, you might need to download the carrier settings for your new carrier.

To see the version of carrier settings on your device, tap Settings > General > About and look next to Carrier. To see additional carrier information, tap the version number. To verify that you have the latest carrier settings installed, contact your carrier."

Step 3 is where it fails :(. When I try to get to update carrier settings, it doesn’t allow me/give me an option to update my carrier settings and I’m trying to ‘push it through’.

I think something is wrong with the SIM card, but I don’t know.

‘thanks MSF 

CallumB If you feel that you have a duff sim: https://help.smarty.co.uk/en/articles/1215834-what-to-do-if-your-sim-card-gets-lost-or-stolen

Don't forget that the existing account will be suspended (for security reasons) until you activate the replacement.

Thanks MSF , I think it must be that, nothing else seems to be working.

thanks so much for your time, and for the link for the link.