pink vertical line on right side of iPhone 13 Pro screen

Unfortunately, the drop may have been "severe" enough to cause this issue. I suggest that you take it to your local Apple Store's Genius Bar or Apple Authorized Service Provider to have them take a look and provide you with your options. Alternately, you can contact Apple Support directly. Simply select the "Get Support" link in the upper right-hand side of this forum's web page.

Per chance, did this iPhone come in contact with any liquid or has been dropped? If neither of these, what have you tried, so far yourself, to resolve this issue?