Thank you for your question.  We cannot diagnose plant problems without clear photos, and/or information about its placement, location and whether its structure is dead.  This species is not known to have many diseases, but a blight has been identified in the Midwest:  https://hyg.ipm.illinois.edu/article.php?id=85

Without photos of its leaves, this is just a "best guess".  Perhaps a visit from a certified arborist would help.  https://www.treesaregood.org/findanarborist/findanarborist

Good luck!