It sounds like you have 2 problems with your clapper. It must be loosely fitting at its hinge allowing it to wobble enough to get caught behind the springs that keep it away from the skirt of the bell except during the strike. The springs should have a broad inverted “T” at the bottom that allows some play of the clapper but prevents it from getting trapped behing the spring. Your clapper may need a shim or large washers at its attachemt to the bell to avoid wobbling. Secondly, you may need new cross pieces (inverted T) at the bottom of each spring in order to prevent the clapper form getting trapped. You will need to remove the clapper to place washers on either side of the clapper attachment and possibly replace the bolt that holds the clapper to the neck of the bell. You should be able to weld, rivet, or bolt as piece of steel across the bottom of each spring to prevent trapping of the clapper.
HJLong, MD