I would suggest never use Myer online, if you order the wrong size or item your in big trouble, hold takes longer than 10 mins and once your through they say they can't cancel the order because its been more than 10 mins
Only website that does this, it's a joke.
Just goto the store and take the item off the shelf. Myer is really really shitty at picking orders quickly, and will cancel if it's out of stock when they finally decided to go get item.
Or just return it in store later