Are you perhaps visiting the Comico website on a mobile device?
Note that if you visit the Comico website on a mobile device, you'll be redirected to the mobile site, which inexplicably does not have the latest chapters. You can go to the footer at the bottom and click "PC버전 보기" to go back to the full site, then you can open the latest chapter.
Side note: It would appear that the mobile site is now somewhat better, in that it actually has all the chapters up to the latest one, Chapter 43. Though like you said, there was probably a slight delay before the latest chapter showed up. But still, at least they're there; there was a time when the mobile site would be something like 5 chapters behind for no reason.
For real? I only recently started reading from comico, so i didn't even know about the delays. I'm reading it on pc so i don't think it was because of that. Now that i think about it, there was a delay on the previous chapter only, chapter 42 i mean, because i got it at about wednesday. I could see chapter 43 late at night on monday, so maybe it was only a slight delay due to time difference, but i got to read it so everything's cool