Welcome back to our Community Forums! Thank you for your post and I'm very sorry to hear that this has been your experience with our Mobile service and that your new SIM card has had some technical issues!
Can you tell us what check's you've carried out to troubleshoot for this issue? Have you rebooted your Mobile device to see if this will work?
Have you tried to put your SIM card into another Mobile phone to see if the same issue will occur on a different handset?
Have you tried to input a different SIM card into your Mobile device to see if this issue will occur with a different SIM card?
Please take a look at our Mobile Troubleshooting page for more helpful tips on what you can do to investigate this issue further. Let us know how you get on and if you need any further assistance after this.