For the future, Jim you really need to ditch this paypal checkout page you’ve been using. It’s 100% useless. You’re making sufficient profit on your sales that you should be able to afford a decent online retail sales portal. It’s 2019 for God’s sake
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Your current checkout page will let you add whatever items you want to your shopping cart, and only upon checking out will tell you the generic message “Sorry your items aren’t available”, leaving the want-to-be purchaser to go back and remove every item from their cart to try to find out what isn’t available, and later re-add their entire order chip by chip, all while inventory quantities are rapidly changing. It makes the purchasing process essentially impossible, especially when combined with rules on chip quantities which the buyer is trying to adhere to. The entire experience is so bad that it puts you off wanting to participate in these sales at all.
As a seller, your customer service is stellar - you are responsive, shipping is reliable, products are good, etc. Your sales portal let’s the process down, however.
Tip: how about having one sale page, with options for adding all of the denominations in the sale, which actually shows the quantities remaining?? This would make the process a little bit less of a guessing game/lottery!
cheers!