When importing orders you may have gotten the following error from shopify.

Shopify Data Request Error: {'price': 'Required parameter missing or invalid'}

This error is sent back from Shopify if the price field is empty. This error may be a little confusing because there are multiple fields called price. If you get this error you should check the line_item.price field as well as the shipping_lines.price field. To fix this you'll need to add a value to the field. If there is no price you can set the field to 0.