Tips on Visiting for Seat Selection Questions

I am planning a long haul flight and want to understand seat options better. I found the Lufthansa Airlines Dulles Office Address, but I am wondering if visiting in person actually helps with getting more detailed information. Has anyone stopped by to ask about seat changes or availability? Did speaking with someone directly make the decision easier? Sometimes it feels better to get guidance from someone who can explain everything clearly. If you have any advice or thoughts about visiting for seat related questions, I would love to hear them.