Earthworms do sleep in a way at night as in they rest and become inactive during the night so they do rest.
However worms do not sleep like us humans do as in the earthworms do not lose consciousness like humans do and nor do earthworms have typical brain wave patterns consistent with sleep like humans do.
So do earthworms sleep? It's a yes and no answer as yes they do sleep but no they earthworms do not sleep like humans do.
But some earthworms such as the night crawler worms come out at night so they are not sleeping at night.
But some earthworms are not active during the night and only are active during the night but it can depend on the earthworms.