Lost silver flute in a brown case with initials A.B. at Riverside Park, Southeast IA.

I lost my silver flute while attending a picnic at Riverside Park in Southeast IA last Saturday. I think I set it down on a bench, and when I went to leave, I completely forgot to pick it up. It's in a brown case with my initials, A.B., engraved on it. I really hope someone finds it!