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The member with MID 136276600 is registered in 2 councils with both units in the same SB account. The MID in your Council is 14677986. Since the is based on the MID in SB, the membership in your unit will show the because MID 136276600 does not appear on your roster.
MID 14296082 is registered in your council so the does not appear on your roster but will appear on the roster for the unit in the “other” council.
This is a function of SB only supporting a single MID.