Have a unit admin look on the individuals profile page the correct account should have their ID number .  All others accounts may be end dated to remove from your roster. If a scout go to membership and end date the membership on the incorrect accounts. On leaders it would be the posistion page

Assure that they show on your roster in my.scouting.org. If not contact council office to check on their registration. If they show in my.scouting but not in scoutbook go to roster . At the bottom of list of names there should be an add scout option, choose it. On the next page DO NOT fill out form rather look for a link that says  connect to existing Scouts in your unit.   click on that and see if scout is available. If this does not work fill out form below

Your logion information is shared between Scoutbook and Scouting,org. Go to scouting.org and try to reset your password there!