Two full built items disappear after selling unit with items while bench full?

I had 3 Neeko's, 2 bows, 1 crit gloves, 1 giant's belt, and 1 GA on my bench for a total of 8 items. I then sold my 2* Lissandra, who had Mittens and Morello's. The Mittens and Morello's disappeared; they weren't anywhere on the map.