I am from Thailand. I applied for the Korea Electronic Travel Authorization K-ETA to enter Korea. At first, the permit was not granted, and when I applied for the second time, the permit was granted. I arrived at Incheon International Airport on a plane with 5 friends with joy, but the immigration officials refused me to enter the country. An immigration official said that the reason for refusal of entry was because I had been rejected 1 or 2 times by K-ETA. All 5 people I went with were people like me who didn't get K-ETA at once. So all five of them were also denied entry. Any explanations were to no avail, and we had to return to Thailand in the end. What are the K-ETA standards? I really wanted to travel to Korea, but I lost my will.