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I have contacts belonging to different groups.
I made a first csv import successfully : I have all data of contacts and they are all in the same big group.
But then I tried to import them group by group with just their email address and the update option. The import seems to be successful. It mentions " Stratégie internet: One contact added to this existing group."
But when I go to group panel, the group has no new contact.
I tried many thing (import more than email for this 2nd import, change group visibility, use a new group, etc.) but it is still the same.