Who I have the same questioned this topic

I bought the Verizon unlocked HTC U12+ from the HTC website. I was a sprint customer, but switched to Verizon to get this phone. I went to the Verizon store last night to switch and port my number over. After the people at the store went thru everything (Signed me with Verizon and ported my number) we realized that i was unable to make calls or receive calls. The people at the store are saying that my phone doesn't have the right CDMA or global network (I believe that was what he called it) but reading on the internet it seems like there might be a possibility that connecting might be a little tricky. I guess I'm just wondering if it's a known issue or I need to go thru HTC and get a new phone sent... I am currently without a phone because of switching carriers and want to resolve this as quickly as possible.