This is normal for some isolated stations where there aren't any other nearby systems, and therefore the mission generation rules don't provide anything.
There are also a few stations (Crevie's Salvo in Kinesi, for example) which don't really have a "missions" service, so they have a mission board to hand-in if they're the destination, but it never has missions on it.
In those cases if you go to a different station you should get missions. If you're at a normal station in the bubble, that's less usual (re-logging won't help, as the missions are stored on Frontier's server) though can happen temporarily in some circumstances.