Hi, I am trying to upload a mailing list based on the downloaded template. I just have erased some not necessary columns. When I tried to upload it I have systematically several error messages: like this one : "duplicate key value violates unique constraint "mailing_subscription_unique_contact_list" DETAIL: Key (contact_id, list_id)=(9257, 2) already exists. "
Any idea in order to resolve it ? Thanks in advance.
PS: I am using the last version 18.3
Does it work with those 'not necessary' columns? Did you remove the External ID/external_id clumn? Did you first export an _importable_ csv/xlsx from Odoo? Got an example set of data that allows reproducing the issue in runbot.odoo.com?