How old are they? Have they played in the actual nesting box before?
I didn't have a nesting box for them. I just had straw laid down in the enclosed part of their coop. I thought they stopped laying as I didn't see anymore eggs in there water dish located in their run. When I went to look at the condition of their enclosed coop area, my heart leaped with Joy as I spotted a pit in the straw, in a corner, shaped similar to a bird's nest - high edges. There was ONE egg IN the nest, and one just on the rim. I started checking it daily, and both my girls, I believe, are laying in it, but not both EVERY day. There's currently 9 eggs.
I received these ducks (White Layers) just a couple days old April 2nd 2018. They started laying in July. Mine are friendly once they got to see what's what and who's who. I've not tried to hold them. They don't seem to be THAT friendly, but they are nowhere NEAR as skittish as my Khaki Campbells. THOSE ducks needed a sedative! LOL.
My ducks have been mating for over a month now - just as soon as I open their pen, they're off to the kiddie pool and stock tank to mate and clean.
I'm thinking of waiting another week and see if one of them will "set" on the eggs. If not, may just put them in the bator. If that's the case, and some do hatch, how easy will it be to introduce them into the parent flock (2 ducks 1 drake)?