I'm sorry that happened to you, but yes definitely try contacting your cc company or Paypal if you used that, and make a missing package case with your post office. I have such mixed emotions on this brand. I have loved the bags I've had by them and that it's a woman run company made in the USA, but I recently purchased a crossbody case on sale. I bought one just like it a few months back on sale as well, and have loved it.
However, when the new one arrived, it had a cheap nylon zipper instead of the excella zippers they used previously. The listing and pictures on their website did not reflect any sort of change in the bag. I wrote them an email requesting to return the bag, and that their listing was deceiving. They granted the refund, but told me that the sale version of the crossbody case had a nylon zipper now, and the full price ones still have the excella zipper.
I looked and the website has two listings for the bag- one full price and one on sale, and all of the details about the bag listed in each one are exactly the same. It seems rather shady to me to cheapen down the sale version of the bag, and still present it as being just like the original. Why even say it's one sale? Just say it's a cheaper version of the original crossbody case. Sorry to derail your issue, I obviously needed to vent my frustration so thanks for reading.

I hope you end up getting a refund. I've heard of similar situations happening, and the buyer ended up getting their money back so I think the odds are good for you for the same.