Vintage AVECMOI Button Down Shirt

Vintage AVECMOI, floral, button down shirt. Size M. Condition: Used, good. There is a rust discoloration on the collar, see photo. Not sure if it can be removed or not, but it would be hidden if the collar was worn down, not buttoned up. Material: 100% Cotton Measurements: (See diagram for location of measurements) Chest - 21" Shoulder - 16" Sleeve - 18.5" Length - 30" front/21" sides/33" back