my chapters have just disappeared on my videos

I'm a new youtuber and made about 25 videos to date. Everything was going well. Daily subs and videos doing incredible consider I had only 400 subs. Then I posted just a normal other video and suddenly I wasn't getting many views and all my chapters I had on my videos were gone overnight. Im convinced my views and subs have stalled because of this. Is this a thing and has anyone any experience with this happening etc. Thanks guys