BT SIM card no service iPhone 12 mini

[Morez]

I have a BT SIM card and I’ve been using it on my iPhone 7 Plus for sometimes without any issues. I got a new iPhone 12 mini yesterday and when I try to use the SIM card on the new iPhone, it keeps giving me No Service. I contacted Apple and they told me to check if it works with WiFi Calls and it does work with that. My phone recognises the SIM card and tells me my number and all the other details but No Service issue is still here. The SIM card works perfectly fine with older Apple devices.

what should I do now? Do I need a new SIM card for the iPhone 12 mini?

[Kate_1]

I think if SIM card works everywhere but not in your Iphone 12, propably it problem with Iphone.

[Morez]

@Kate_1 It may be but as I said, the phone recognises the sim and I think the problem is with the 5G feature of the IPhone 12. Do the 5G phones need a new sim? Because the Apple Advisor told me that the SIM card may be incompatible with the new iPhone 

[Carlusha]

@Morez  Have you tried turning off the 5g in the phone's settings to see whether that has any effect?

[Morez]

@Carlusha yes I did but still No Service