How emails are sent: Lukrena's sending or your own SendGrid
Invitations, reminders and sales emails are sent through Lukrena's sending service by default, within the monthly plan limit. Your own SendGrid key (Ustawienia (Settings), Pozostałe (Other)) is optional: with it, emails go out from your own domain and SendGrid account. The sender and reply-to address are set in the same place, and the signature comes from the brand settings. If your own email tool runs alongside, check that it does not send the same reminders a second time.
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