hello, I have created a modpack that I played with a couple of my friends, but I wanted to change out one of the mods for another one, when I did that it said that the mod is missing and the world is generated with it, or something like that. At first I thought that I have to add the mod again, but it didnt work. I had a backup from a few hours before so I rolled back and the mod was back. BUT now I still cant start the server and I get this:
How can I fix it without deleting this world, as I have ~1.5 days in-game it would be really sad. Thank you 
