Its a
Cud or moved meatl from the 3 caused a brokendie or worn die, that is my guess, I am not a error expert sorry , but I would like to know what it is for sure my self. Also unless I misunderstand the term Bie-cent it would have to have the
Cud inbetween the letters B-//-I. there are others as well between all of the leters in the word liberty on cents with Bie being the most collected