Ask them. I've actually had some good responses from ebay when I've had questions. The receipt idea sounds good but ask them. Did you use your own photos? Or photos that belonged to the bag company? Once you know the reason, you should be able to find a way to fix the situation. They may even have a suggestion.
The unscrupulous ebayers (especially those ones that use "five finger discounts" and those that charge ridiculous shipping have caused a lot of problems for those of us honest ones out there.