Unless something is keeping one of the cups from going in far enough, try over-tightening the adjustable cup so the spindle turns a bit hard before tightening the lockring. When the lockring tightens against the BB shell ,the adjustable cup will be pulled out a little due to the tolerances in the threads. If you tighten the adjustable cup so the spindle turns smooth & then tighten the lockring, you're going to have some play. It's a trial and error thing.