Looking for advice: My authentic Mikimoto pearls won't sell on eBay: what am I doing wrong?

Any advice?

Do you have multiple clear photos, accurate description, and is your listing price reasonable? (You can check sold listings on eBay for what similar items have sold for, for comparison.)
If so, it may just take some time for the item to sell.

Things I look at when perusing eBay:

Do you have a seller history or is this your one and only auction? Do you have positive feedback?
Is the price of shipping too high?
Do you accept returns?

Could we see the listing?

Please show us the listing.

Are you in Japan? When I look at "authentic Mikimoto" on eBay, many of the items are in Japan. I don't know if there are tariffs, but the shipping is very high.

Sorry for going MIA! I wasn't sure if sharing a link would violate forum rules.

I ended up sending my pearls to Unvault along with the original Mikimoto invoice showing a ~$9,000 purchase price, but their top offer was only $228! Needless to say, I'm having them returned. Once I get them back, I'm going to list them on eBay—I'm aiming to get around $1,700–$2,500 for them.

For context, I'm not located in Japan, but I bought them directly from the official website. Thanks for your patience, and I'll post the eBay listing here soon so you all can check it out and let me know what you think!