We typically don’t allow any more than 5000 unique contacts and purchased list are not permitted on our platform.
There is currently a 5000 unique contacts limit to keep email sending reputation strong, prevents us and you from being added to SPAM lists and makes the platform more effective for all customers.
You many need to update your subscription level to import more contacts. Contact
Note: Unsubscribes are not included in your 5000 contact's count