wait a sec. in your post you said it ends after 48h. since you didnt described it more clearly I assume that the auction ended either 48h after creating the first post (even though there was no end time at this point) or after you added the new end time. in both cases the auction has already ended. Since you didnt write something like " 48h after start" there is no way from a buyer to see that you mean it that way.