Hope you are doing well.
I’m sorry to hear your having a with a black vertical line on your TV. The black vertical line on your TV is due to damage during shipping or transporting home. In this case the best option is to contact 1-800-SAMSUNG for a replacement (if they deem under warranty) If your TV is still under warranty I would take it back to wherever you made the purchased from and ask for an exchange. I’m very sorry for your inconvenience and hopefully that answer your question.
Hope I was able to help you and good luck.