Hi ​@Louise Kay 

Have you tried turning your phone off and then on again? (Simple but sometimes it’s the solution to the problem)
iD advise ‘wait until 10pm on the port-in date and then restart your phone for all to complete successfully’.

You can also check the phones settings to ensure they are correct:-
https://www.idmobile.co.uk/help-and-advice/get-your-settings

If you are still having problems then let us know what phone you have and we can maybe point you in the right direction.

Good luck x

I had similar problem which had me getting really frustrated. Eventually I found that, because I’d opted for physical SIM card, but when phone arrived set up gave me option of rain. I chose that and was instantly up and running for a few days. Did you do same? If so I found solution was settings, mobile data. This showed I had personal and business settings. Same number but clearly one was dim and one was eSIM. Sorted by turning one of them off.  Hope that helps

Hi ​@Louise Kay 

Sorry to hear this, what device are you using the SIM card in?

Have you tried a device reboot? Removing the SIM and re-inserting it?

Tom