(4) On Apr 1, 2018, received $24,000 cash in advance from a customer to play in the play area for one year. The customer can play in the play area from Apr 1, 2018 to Mar 31, 2019. The cash receipt was correctly recorded on Apr 1. On Dec 31, 2018, the customer's rights to play in the play area have expired for 9 months. Make the corresponding adjusting entry