This land support has the plains subtype. This land is neither a plains nor does it convert gems to white.
To clarify, is this card not functioning properly with effects reliant on the Plains subtype?
Additionally, this card is currently listed as converting gems to Blue or Green. Is this card’s conversion effect not working as expected for you?
The card functions correctly when in play, but should not be considered a plains for effects that care about land types. (I’m not sure if any card currently does care about plains, but just being proactive)