I know that lezhin handles chapters weirdly, but it seems like their usual process doesnt apply to this webcomic fortunately! Another reference to look at is at the original korean version where all chapters are still free despite it having so many of them haha. (=・ω・=)
To add more to it here's the link if you want to check! Currently there is 189 chapters out with 181 free total doing the usual wait a week system. https://www.lezhin.com/ko/comic/ImmortalDays
Oh good. Also, happy to see that there's still a lot more story to come.
19 more days until the last episode of season 1 will be available for free. I'm not sure how they'll handle it here but they usually lock the chapters for the season again once the entire season was available for free for one week. So if you want to read this story (without having to pay) you should do it soon.