for people who are panicking about their lost lists

They aren't deleted you'll get them back.
don't worry, ppl whose acc were made in 2014 and 2015, as in earlier years, slowly got their reads back.
Currently 2017 users are getting it back, its a very slow process as the site is adding it one by one rather than instantly giving your reading list back, so be patient if your account was made in the last few years, it'll take atleast a day or more. Some accounts that are proof of ppl who get their stuff back :
https://www.mangago.me/home/people/65330/home/
https://www.mangago.me/home/people/7934/home/
https://www.mangago.me/home/people/12004/home/

currently only already read stories are added, i haven't seen anyone who got their stories from the other two sections but i beleive those will be added too, very soon.

so yeahh it'll take quite some time but you'll get them back.
also once they're back, in case you're looking for ways to save them perhaps in an excel file, I've made a tutorial on how to do it easily and quickly rather than having to enter everything manually one by one, so if you'd like, you can check it out.

https://docs.google.com/document/d/14Drj0CviUhrAmZlU-DC-AtxGFQoH1_PYQ81b2Vzu82w/edit?tab=t.0