I had a Galaxy S7 Edge and just bought this S10 5G last week. It arrived a couple of days ago. Everything seemed to go fine. Setup finished, all my contacts and apps transferred. Then I noticed I wasn't getting text messages back. I turned on my old phone, and there were all the replies to the messages I sent from my new phone, along with "Activation Incomplete" at the top of the old phone.
I googled a bit and tried to activate from my verizon account online. When I entered my SIM ID, it said that it couldn't be activated.
How can I switch the calls and messages to my new phone instead of my old one? Why did this happen? It'd really be a pain to have to go to a Verizon store. I live pretty far out in the countryside.
Did you activate the new phone using a preinstalled SIM card? If so, turn off the old phone and remove the SIM card from the old phone.