Activation of iPhone 12

I am having trouble activating my new iPhone 12. I have an existing iPhone 8 with Verizon service. Bought new iPhone 12 from Apple and had it shipped with Verizon sim card. I tried to follow instructions from Apple on how to activate. This process was not successful. When I turned on new phone to first activate with Verizon, the process never asked for my existing phone number and consequently when I completed the steps the phone will not send or receive calls. Do I have to go to Verizon store to get fixed or is there something I can do to get this operating properly?

Thanks very much for any help.