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We moved between councils about a year ago. My son in Scouts BSA was set up to log in to Scoutbook in the prior council. However, since the move he still just see his prior council which is now dormant. I tried logging into MyScouting with his information to switch his active profile, like I did as an adult. That does not seem to work for youth.
Old BSA ID (Last Frontier): 133362549
New BSA ID (Sam Houston): 137219968
The problem is that after you moved, your son did not change the BSA Member ID (MID on his my.scouting.org account. This causes the system to create another Scoutbook ID with the old MID.
I have added the new MID to his my.scouting.org ID as primary. Please ask him to log in to Scoutbook again and confirm he sees the account with all of his advancement.
Thank you, Ed. I tried logging into my.scouting.org with his info, but the “Manage Member ID” section looked different. I thought this meant it was not an available feature for youth. Maybe I did this too soon after the transfer. I just logged in now and see both memberships, just like an adult account. I learned something new.