[V] Curtains lighting and colors incorrect when placed inside

The beautiful curtains from the Vampires pack are cast in a constant shadow when placed indoors. Their lighting and colors appear correct when placed outside. But when placed inside in a well lit room, their lighting darkens, their colors are so muted they appear gray. Even when using direct lighting, like spotlights, the Vampire curtains still look dark and dull inside. This issue doesn't happen with any other curtains. Could this please get fixed?

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