My sims have finished the baby challenge but now when we click on the bassinet it says they want privacy?

When a Sim needs more privacy, it is generally because there is a child in the room. If you get this message when clicking on the basinet, you can temporarily move it to a quiet room. When this happens in a bathroom, you can use an empty bathroom, or temporarily move the object from the room.

you need a double bed and both sides need to be unblocked so they can both enter the bed and no one can be in the room even the romantic partner