People shop for cars after work. The question about a white hybrid comes in through the website chat at 10:12 p.m., a Messenger message about lease terms lands on Sunday afternoon, and an Instagram DM asks about a trade-in during the late game. Your BDC opens at 9 a.m., and an autoresponder that says "we'll get back to you" is the kind of reply shoppers learn to ignore.
Overnight leads also arrive with nothing attached. In the morning the team works a pile of "is this available?" messages with no names, no timelines and no phone numbers, and spends the first hour of the day asking questions the shopper would happily have answered last night.
The shoppers did not stop shopping while you were closed. They messaged the next store too, and whoever answered properly first is now the one they plan to visit.