My world gets deleted when logging back on

Whenever i play Minecraft and im ready to stop playing i exit the game by saving and quitting and then turning off my pc. But then when i go back on Minecraft the latest world i played gets deleted but my other worlds are fine but it resets the key binds and the Fov. But if i don't turn off my pc i can go on Minecraft and everything will be fine. But i now make a copy of my world when i realized that happened. But its still annoying to change my Fov and my key bind every time i go onto the game.