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. On October 2012, the Plaintiff entered into a membership agreement with the Defendant (hereinafter “instant contract”) on the F Card (hereinafter “the instant card”) issued by the Defendant via the Internet regardless of the aforementioned division and trade name change (hereinafter “Defendant”) on September 1, 2014, where E Company was established as a company division and received the rights and obligations on the part of the credit card business operated by E Company D, and E Company changed to the Defendant on December 1, 2014.

The annual fee for the credit card is KRW 100,000 (basic annual membership fee of KRW 5,000, annual membership fee of KRW 95,000), and the Defendant agreed to provide additional services, such as providing the card use amount of KRW 20,000 per 1,50,000, in addition to services arising from the original function of the credit card.

The Plaintiff was issued a credit card listed in the separate sheet according to the instant contract.

(A) The Plaintiff asserted that the term of validity at the time of filing the lawsuit was until May 31, 2018 and filed a claim for future implementation until that time. However, according to the Plaintiff’s preparatory brief dated December 2, 2015, the term of validity of the credit card issued by the Plaintiff under the instant contract is April 2018).

Around February 26, 2013, the Defendant announced that C mileages offered to the instant card members on the Defendant’s Internet website, etc. are changed to 1.8ma days per 1,500 won per card use amount from September 1, 2013, and the changed C mileages were provided from September 1, 2013.

From September 1, 2013 to April 30, 2015, the Plaintiff was provided with mileage 210,897 C at the rate of mileage accumulation changed from the Defendant.

C. On December 13, 2010, the Defendant modified the Defendant’s standard terms and conditions for personal members, and under Article 14(3), “Additional services, such as points and discount benefits, offered at the time of the use of a credit card, are maintained without reduction or abolition for at least one year after the new withdrawal of the credit card, and changes in additional services.