It happened when I switched from draw mode to edit mode to adjust a drawing. When I did this I noticed the layers go missing from the bottom 'stroke' timeline panel and not come back when I went back to draw mode. It's the panel that says summary and usually has the layers/ keyframes in and you can scrub through the animation. I don't know what I accidentally clicked to do that but I want them back so I can animate easier.
There should be a green thing going across too showing the timeline of it but there's nothing. Any ideas how to sort this? I'm new to Blender and know some stuff through tutorials but nothing's coming up on how to sort this out. Opening a new file has the layers immediately there.