I lost my Account Datas, Recourcepacks, Saves, Skins and more, but the data on the Servers are still there.

I started the minecraft Launcher and couldn't do anything. As I started the minecraft Launcher again there were none of my Skins and no Installations but I still had my Account and the Datas on the Servers (Hypixel, SpieleOase, GommeHD, ...). Can anyone help me?