Why is my cellular series 6 watch not capable for its cellular data?

my series 6 watch is not able to connect to its cellular data so I’m unable to use my watch to its original nature. I have tried to connect cellular data to the watch by guiding myself through the watch app on my iPhone but it alerts me saying it is unable to connect and to click the link which takes me to my Verizon and add cellular data to my plan when it already is apart of my plan which I also already pay for? Need help please? Has anyone experienced this?