I equipped on line staff

I have been trying since a few weeks ago to make a purchase on-line - the transaction keeps failing. I called Crocs and no one knows what the problem is. Once, a woman suggested that the Voucher code I received when I signed up for the newsletter cannot be used for items that are on special...but the worst thing is is the poor service received from the on line staff - unhelpful, rude and honestly are not equipped to resolve issues