Deleted mangas in reading lists???

Are we going to get them all back? I had 1100+ mangas in there that I wanted to keep following and a few months ago all of them were just gone. Now maybe 300+ remain and I can't fully remember which were the ones I was following back then (I just know I really liked them!).
I'm pretty upset mostly because they are precious memories to me and also because it really helped me keep track of what I'd already read/what I was saving to re-read or binge-read (when they had more chapters).
Is there any way to get those mangas back or are they lost forever?