I also had an issue with an auction from a very good seller. He listed a seedling but when it came time to ship it to me, he realized that he had listed the wrong cross, so the auction seedling that I won, did not exist. The seller gave me the option of a refund or picking a different seedling (which is what I chose). I was disappointed, but do love the seedlings that I did receive in the end.
Where would be the protection on Facebook?