According to Merriam-Webster, ju-jube is the pronunciation used for the fruit or tree, and ju-ju-be is a fruit-flavored gumdrop or lozenge.
ju·jube | \ ˈjü-ˌjüb , especially for sense 1 ˈjü-ju̇-ˌbē \
Definition of jujube
1 : a fruit-flavored gumdrop or lozenge, especially one that is made from the jujube fruit and has been used as a remedy for various throat conditions
2a : an edible drupaceous fruit of any of several trees (genus Ziziphus ) of the buckthorn family especially one of an Asian tree ( Z. jujuba )
b : a tree producing this fruit