Hello @MillionairesC9. I'm very sorry that you were having trouble with your automated birthday campaign. I see that you did have a chat with one of our Support agent to discuss this issue.
It looks like your automated birthday email was scheduled to go out three days before a contact's birthday. Let's go through a couple of scenarios.
Say a contact has a birthday of August 24th. If their birthday is updated in the account on August 22nd, then they would not receive the automated birthday email since there was no birthday information in the account on August 21st (the send date). This seemed to be the case for some of the contacts that didn't receive your automated email.
If a contact has a birthday after that date, say September 4th, and their birthday was updated on August 22nd, they would receive the email three days before their birthday on September 1st.
If a contact had a birthday of August 4th, they would not receive the birthday email until August 1, 2017 since their birthday had already passed before you updated their birthday date in the account.
Hope this helps!
Caitlin M. Community & Social Media Support
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