Hello @ScoreChapter180 ,
If a particular email address seems suspicious upon being added to your account, through a sign up form you've made through us, then our system may flag it as Temporary Hold for a time. Additionally, if an account has Confirm-Opt-In turned on for their account, incoming contacts that haven't clicked the coded link in their confirmation emails will stay as Temp Hold until they've done so.
For more info on large Temp Hold contacts, I'd recommend perusing this article and its associated redirect links.
Advanced Email Permissions
Confirm Opt In
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