Problem: You have unbillable materials/activities (price of $0.00) showing up on invoices along with invoice dates.
Solution: You've likely set the billing settings incorrectly. Items set to Bill Per App or Per Unit are designed to show up on invoices for billing. Instead, set the Invoice type to Unbillable - since the price is $0.00 - we can assume these activities are not billable. Make sure the Show Service Dates is also set to unchecked.