On December $20,2023,$ Lucille Corp sold merchandise at a price of $$6,000$ on account. Lucille delivered the merchandise on December $20$ but they offer a $30-$day return window. Based on historical data, Lucille estimates $10\%$ of the merchandise will be returned. As of December $31,2023,$ $$400$ worth of merchandise has been returned. On January $5,2024,$ $$100$ worth of merchandise is returned.

Please write the correct journal entry for this and PLEASE EXPLAIN each step properly. My teacher's explanation is not fully correct. I am confused with this part. Why is she not recording one entry as estimated sales returns and why is she adding refund liability?

CHAPTER $7-$ ACCOUNTS RECEIVABLES $-$ SALES RETURNS

December $20-31$: $$100$ worth of goods returned

$$400$ worth of goods returned

$2023-$ Actual return of CY sales $($$$400)$

CHAPTER $7-$ ACCOUNTS RECEIVABLES $-$ SALES RETURNS

December $20$:

January $1-19$:

Sold $$6,000$

$$200$ worth of goods

$2023-$ Estimated return of CY sale $($$$200)$

CHAPTER $7-$ ACCOUNTS RECEIVABLES $-$ SALES RETURNS

$$400$ worth of goods returned

$2024-$ Actual return of PY sale $($$$100)$