sellItem() doesn't really appear to be working in 2021? sellItem(Box) works fine in opening the interface, but much of the time sellItems() just returns false having failed. I'm writing a merching script and having to rewrite wrappers around all these methods (eg. also around getOverallPrice() which randomly NPEs from time to time) is frustrating. Let me know if it's my fault -- short context on how I'm using it is below. Help much appreciated! Maybe it is also failing in a similar way nowadays for others.
if (free_box != null){
log("found free box to bigSell in: " + free_box);
getGrandExchange().sellItems(free_box);
log("opened sell interface");
sleep(approx(3000));
boolean sold = getGrandExchange().sellItem(name2id(itemName), price, (int) this.inventory.getAmount(itemName));