Is there a way to change profile photo when posting on Facebook?

Ok, a tough-to-explain problem. I am trying to post my Rover link on various Facebook pages. When I copy the link, Facebook automatically adds a photo, title, and the beginning of my profile description (like Facebook usually does). However, for some reason it uses my old profile cover photo instead of my new one. I even tried deleting the old cover photo from my Rover profile entirely, but it still uses it. There's also no option that I can see to change the photo that Facebook uses. Not sure if anyone has any ideas since it's such a specific issue.