Why the Fee?
A $0.20 fee is automatically added to orders totaling less than $10. This covers transaction processing costs for smaller orders and is shown at checkout for transparency.
How Can I Avoid The Fee?
The easiest way to skip the fee is to have an order value higher than $10. Bumping your order total to $10 or above will automatically remove the 20-cent charge.
Consider fulfilling multiple orders together using the Bulk Fulfillment feature. This will total the charge larger than $10 and eliminate the Small Order Fee.
You can learn more about this here.