As you mentioned, you're missing a pin. This bracelet appears to my eyes to require two spring bars and 4 pins to hold it in place. You might be missing a pin and a springbar. I think you need some additional parts. These parts are generally fairly inexpensive. The last time I went to a JLC store, they gave me free spring bars after I told them I had lost one. I think this was the London store on BOND street if I recall correctly. Many thanks to the lovely, efficient, quick, and generous Asian lady at the London boutique (there might be more than one person there who meets that description).