Thank you for the question. Unfortunately I can't really tell much from the photo because the plant is so damaged. I think I see some 1/2 round dead areas on the edges of some of the leaves so maybe it has succumbed to Lupine anthracnose. Treatment is to remove the plant and treat nearby plants with a fungicide. Read about it here: https://negreenhouseupdate.info/photos/lupine-lupine-anthracnose. This is more of a problem in wet weather which we have had lately.
Another possibility is damage from herbicide drift. Sometimes an herbicide is sprayed elsewhere and drifts in with unintended consequences.
Thank you for contacting Extension.