This error is because of a missing attribute however it can sometimes be unclear which Walmart attribute is missing.
“Key Features” is actually “Bullet Points” in StoreAutomator. An item can’t be created on Walmart without bullet points.
To fix this error, you need to complete your Bullet Points by editing your item in StoreAutomator. Make sure that you select the Walmart channel.
Here are the steps to follow:
1-Click the pen icon “Edit”.
2-Click the “Tags” tab and click the “Override” button then fill out any empty Bullet Points.
If your product already has bullet points please contact Support and create a ticket.