The same novel and the same thing has happened.
Chapters locked again
Same here.
Same where. Why? 
It happend on other novels as well. Why?
They are just stealing money at this point....
So if I want to read the story again from the beginning (which I do for most of my favorites once in a while) I have to pay for each of the chapters I already read? Nope. Not happening. Unfortunately, this won't be the first time that this has happened, either. Lame.
So we have to open all chapter that locked to read new chapter ?
I have had this happen to nearly every novel in my library and at least now I know it's not only me. Wonder if Webnovel will ever give us an answer on this or if it's gonna just get swept under the rug like almost every other bug and issue I've run into. The quality of customer service really sucks.
Ariankentara Answer is simple. You did not spend SS to unlock it previously. It was unlocked for free back then and they have just been retroactively locked.
CKtalon I understand about the ones that started out free, but this has even happened with novels that I have purchased the chapters on. And before you ask yes I did go back and check my spirit stone history, I now have quite a few entries there showing that I have purchased the same chapters multiple times. This isn't the first time I have had this happen either. It's rather frustrating especially when half of the time the links to purchase spirit stones don't work. They don't work on either version of the app I have, internet explorer, or Google chrome for me. Ugh 
Ariankentara Post some screenshots and your User ID number. You can host your pictures at http://imgur.com
I'll get a dev to look into it.
CKtalon this shouldnt be happening this just feels like we are renting novels. btw history resets every 60 days so what do i do with he chapters that i unlocked before... ill never get the moneys worth i used on those...
This happened to me as well with advent of the archmage chapter 229-266.
I haven't checked the other books I'm my library yet.
MysteryOriginal It's a permanent purchase. I've not had any of the chapters I purchased revert back to lock. Most of the time, those chapters were never "paid for with SS," but were released for free.
CKtalon if that was the case i wouldnt be complainibg here...
MysteryOriginal Do you have the logs to show that you purchased those?
CKtalon yo, what happened after my chat to you and I even chatted to dev he was going to get as well that was 2 weeks ago,
i showed my posted screen pic's and I give my id etc,
you were going to get back to be over a month ago ???
should I be reporting this to PayPal and asking for my cash back ( as I trust no internet company ),
as on top of my missing unlocks which you saw and we chat in this forums about,
today I basically work out that the novel I was buying gifts for seems to be dumped bt the tl team with no warning after gifting today as well I can remember all the QI CSR's comments on novelupdates say qi is the best etc ...oddly i still have those screen pics from the post before it was added to the mega post on novelupdates
You should try to encourage us... We unlock chapters instead you lock them... It's so discouraging....
- Edited
Pizz IIRC, the 1SS chapters were a problem with the backend, which made those TNC chapters 1 SS. Since it was Webnovel's fault, they are honoring their price mistake. Which I assume you still have them unlocked.
As for the others, it seems like you just didn't purchase those chapters.
FYI, no one is going on NU to do CSR stuff. NU figures very little in the big scheme of things already. Only a few translators will go there to stir up drama for the lulz, but it's done openly with their nicks.