Vertical Line in center of screen

Question

All of a sudden my tv only displays a 3/4 inch line down the center of the screen. the sound works fine and changes when I change the channel on the remote. I called a television service professional and was told that it may be a "vertical card". Researching this "card" online had yielded 0 results. I however have found several suggestions based on the same problem only with a Horizontal line. now I do not know if this card exists or if it is a componet that can be easily replaced. if anyone here has any information that may help me with this problem please reply