There is a mini case below, please state the financial reporting error and provide a solution.

The industry standard for shoe returns is 20 days, subject to a 10% restocking fee. NIKE is using these same terms for the new super shoes At December 31, 2019 there were $500,00 sales of these shoes that were still under the refund return period. NIKE only started selling these shoes in October of this year and as such still does not have an estimate of the amount of returns. Currently, no accounting has been done regarding potential returns of these lights.

What is the financial reporting error? Please provide a solution to this error.