Hello @RobDeFrancesco ,
Contacts become suspended when our system receives a non-existent bounce report from the receiving network or email program. After enough of these bounces, whether it's you or someone else using our system to send to that address, our system will set the address to "suspended."
If you believe these contacts are actually viable, you're welcome to try unsuspending them in your account, and resend / quicksend to them. If we get another non-existent bounce report, they'll go back into suspension. If you're needing a very large number of them unsuspended in bulk, then I'd recommend speaking with our Delivery team so they can do a mass unsuspend and collect info on why so many allegedly viable contacts bounced as non-existent enough to trigger suspension.
If you're less interested in unsuspending them, so much as simply archiving them, then I'd honestly recommend exporting them, and either uploading that export file as an unsubscribe import or delete them from your account entirely. If they remain in your account, then they'll still be contributing to your account's active, billable contacts. Exporting them will allow you to maintain a XLS or CSV file with their info in your own system. Unsubscribing them will allow them to remain in your account, but set them as inactive type so they don't contribute toward your billable total. Only deleting them will simply remove them from your account, but allow them to be easily re-uploaded as an active contact back into your account, regardless of whether the bounce has been addressed.
See also:
Managing bounced contacts
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