Lost vintage 1980s baseball card in Riverside Park, Great Falls.

I lost a vintage baseball card from the 1980s while walking my dog in Riverside Park, Great Falls. It features my favorite player, and the card has sentimental value as it was gifted to me by my grandfather. I think it may have slipped from my pocket when I was handling the leash. If anyone finds it, I'd really appreciate a message. Thank you!