Before the new 1.15 updated I had a modded survival world in mc version 1.12.2 with multiple mods and had no problem until today when I came back to play my world it was gone and every other world I had was gone as well. I re-installed forge for 1.12.2 because my mods weren't showing up either but no matter what I do they still don't show up.
I don't care about getting my world back since I gave up trying, I just want my mods to show up and work. I tried deleting everything in my mods folder and putting my mods back in but still nothing happened. I don't know what to do now.