We are onboarding MKTO, transferring data over from RE to begin IP warming, and have created lists of most engaged people to input into MKTO to send to. I have one list of 4,000 people, all unsub=empty in the .csv column. I have written the email, and am sending through a prgoram to send to that list that I have just imported.
Every single one of them are blocked from emails.
Any idea where the issue might be?