If you have any questions or concerns about lost items, travel, or anything else airport-related. You're not sure how to get in touch with customer service at KLM Dulles Airport, but you can find out more information by doing so. I contacted KLM at Washington Dulles Airport in this manner. Then go to the official KLM website, scroll down, find the assistance section to get the number, and give the KLM Washington Dulles Airport Phone Number at +1-802-610-2076 to talk to an airline person. https://www.travoflyers.com/blog/klm-washington-airport