Since the company is not large enough to occupy the entire building it owns, it rented space to a tenant at $$2,600$ per month, starting on November $1.$ The rent was paid on time on November $1,$ and the amount received was credited to Rent Revenue. However, the tenant has not paid the December rent. The company has worked out an agreement with the tenant, who has promised to pay both December and January rent in full on January $31.$ Record the receipt of two months rent on January $31.$