couple of things the groove the needle goes in at the bed, very clean
shuttle carrier is against the race tight to snug . loosen the screw under the bed and on the long arm, push the carrier to the race.
tip of the shuttle / hook is also against . if not it could be the wrong shuttle
shuttle has to be loose in the carrier..
eye of the needle just below the point / tip of the shuttle. if your needle has a scarf I like to set then half way on the scarf . these needle heights on long bobbin can be a lot father below the tip than on round bobbins, they have nothing to hit ..
and when doing this you have the thread from the bobbin laying on the bed, Do Not hold it tight . like you would a round bobbin machine. if you do it will not form the loop