Hi rjs - Welcome!!
MaG is right, every detail must be correct. Be very careful about which herb you select - the one you need is in a drawer with a smudged label.
It's on the right side of the cabinet, third from the bottom (I think)
Be sure you put the charcoal and styrax in the incense burner and light them, before doing the other part.
Be sure you really have the correct ashes. There are thousands of jugs in the room, and the one you need is on the very far left row.