If you say that something duly happened or was done, you mean that it was expected to happen or was requested, and it did happen or it was done. Westcott appealed to Waite for an apology, which he duly received
Not bright or clear to the eye; wanting in liveliness of color or luster; not vivid; obscure; dim; as, a dull fire or lamp; a dull red or yellow; a dull mirror
If something is duly done, it is done in the correct way. the duly elected president of the country
Furnishing little delight, spirit, or variety; uninteresting; tedious; cheerless; gloomy; melancholy; depressing; as, a dull story or sermon; a dull occupation or period; hence, cloudy; overcast; as, a dull day