Why not 24

In the early hours of Sunday morning at about 3am I went to the McDonald's in Florida that should be a 24 hours MacDonald's but they where closed despite there being staff in the shop.

No information provided a time just a staff member at the window indicating with her hand that the shop was closed. How can they indicate that they are 24 hours if not and why then was there staff members in the shop at that time of the morning.

The state of disaster is over and if they indicate they are 24 hours they must be 24 hours.