I have the same issue too.  I want to adjust the start and buy now prices on one of my listings (which ends in 24 hours) to try encourage bidding to start (so no bids have been made as yet), but both those boxes are grayed out on the desktop app.   On my Android phone, the Buy Now cannot be modified but the start price can, but then when I try to update the listing it tells me I can't change the start price.   I've never had this issue before, so it's a new bug TradeMe.   Please fix urgently.