no service/constantly loses service

I have an Iphone 12 pro 512 GB with verizon service. I'm currently using the sim card that shipped with the phone. I am having a problem of losing service every time I use the elevator in the hotel where I work. I toggle my phone off and on Airplane mode to regain service each time I exit the elevator to fix it. I work in a 33 floor hotel in Las Vegas where there has always been good service inside the building. There has never been service inside the elevators but as soon as I would come out onto a floor my previous iphone 11 would automatically connect. The iphone 12 does not. I have tried resetting the phone with no luck. Its very frustrating since I am up and down the elevators all day at work. There is 5G service outside the building but just LTE inside. I do not seem to have any problems losing service while driving around or at home so Im very confused. Any one else having these issues with "NO SERVICE"?

Any suggestions are appreciated, thanks