How can eBay compete with Marketplace and others. Sales down for me. Any suggestions?

[willowrockcountrystore]

Sales down for me for the past 6 months. I've always had an amazing Christmas season. This one was worse them July sales. I do sell mainly books, some other stuff. I had to reduce my store size, just isn't paying for itself. I've been selling for a long time, worse year yet. I know pandemic and Covid, but other venues are selling fine. Ebay is my home, just want to be successful here. 

Thanks for any tip and tricks THANKS