You can try adding a new string to replace the broken one @spOt123 by tying the new one into the bracelet instead of the broken string (similarly to an alpha) and once you keep working on the bracelet, the new string will stay put the more knots that are tied with it. This might be challenging though depending on where the string broke. Or, if the bracelet is in an early stage of completion, maybe it would be easier to start again using the same string. Sorry that your string broke!
-dangeli-
