I've had my Amazon Merch account a few years now and for the most part it works flawlessly. However, lately, I am unable to post more than just one image. I'm using a saved template, so nothing changes. I'll successfully upload one image, then after that, the review button is grayed out. My images are all made using templates, so the sizes are spot on.
What could be causing this to happen? So frustrating! I wish it would at least tell me if there was an error.