1. The defendant's appeal and the plaintiff's incidental appeal are all dismissed.

2. Costs arising from an appeal and an incidental appeal shall be respectively.

1. Basic facts

A. (1) On August 2012, 2012, the Plaintiff entered into a credit card membership agreement with the Defendant (D) (hereinafter “Defendant”) and changed the name to “B Co., Ltd. (Defendant”) by absorbing F Co., Ltd. and “B Co., Ltd. (Defendant)” without distinguishing between “B” and “B Co., Ltd. (Defendant)” and “Defendant”, after dividing the company into E and establishing E Co., Ltd. on September 1, 2014.

G card (a credit card newly issued on April 26, 201) between the Company and the G card.

hereinafter referred to as “instant card”).

) A credit card holder subscription contract (hereinafter referred to as “instant contract”).

(2) The term of validity of the instant card issued by the Plaintiff is up to September 30, 2017, and annual fee is KRW 100,000.

At the time of the instant contract, the Defendant agreed to provide additional services, including the accumulation of C mileage (it may be converted to J or K mileage) at the rate of 2 math day per 1,500 won per use, in addition to services arising from the original function of the credit card.

B. On February 26, 2013, the Defendant changed the percentage of mileage accumulation, which was provided to the members of the instant card from September 1, 2013 on the Internet website, notice, etc., announced that the rate of mileage accumulation is reduced to 1.8 C mileage per 1,500 won per 1,50 won.

Accordingly, from September 1, 2013 to April 30, 2015, the Defendant provided C mileage to the Plaintiff according to the reduced rate of accumulation.

C. Article 14 ( Points and Other Services) (3) of the Terms and Conditions related to the instant contract provides at the time of the use of a credit card, additional services, such as points and discount benefits, shall be maintained without reduction or abolition for at least one year after the new withdrawal of the credit card, and when any change in additional services is made, six months after the date of change.