I would take it all apart and start over, Make sure your ball bearings are the right size. Loose bearings are better than caged bearings. Make sure the drive side cup is fully seated all the way down into the bottom bracket shell. Tighten the adjustable side cup all the way down until the axle has significant resistance to turning before tightening the lock ring. I always assemble my loose cone bottom brackets way tighter than common sense would consider necessary. It's been my experience that if I don't overtighten this assembly at first, I'll have to come back and tighten it up later. Crankshaft forces are strong. Things can loosen up down there.