It stopped working after I wound the bobbin! Elna super?

I have a very old Elna super, I’ve used it for a few years and I’ve never had a manual. I re wound my bobbin like I’ve done for years, I put the new bobbin on the bobbin winder on top of the machine, push it to the right and loosen the wheel on the side of the machine to stop the needle from going up and down as I wind the bobbin, when I was done I put the bobbin winder back to the left but I couldn’t re tighten the wheel. If I step on the petal the outer wheel spins but the only way to move the needle it to manually turn the inner wheel, I’ve hade this problem before but I cant remember how to fix it, please help!