Hello @cap4pets ,
Without seeing the actual error message, I can't really offer specific insight. If the email was going to your full list, and was already in the process of sending (aka Active status and sending in stages) then it wouldn't have been available to cancel without explicitly calling in to address. Based on your description however, it sounds like that shouldn't have been the situation.
If the issue occurs again, I'd advise calling general support when they're open. If it's another early morning sendout, then I'd advise pinging Chat support (open overnight), or calling phone support right away when they open. That way we can observe the error and behavior live, and work to address it. For phone and chat support's hours, please see our main contact support page, also available via the Help tab of your account.
... View more
