MailPoet – Poor deliverability rate

Hi, our MailPoet has stopped working and is displaying this message:

Sending has been paused due to a technical issue with MailPoet: MailPoet Sending Service has been temporarily suspended for you site due to degraded email deliverability. Please contact our support team to resolve the issue.

However, we are not a premium member therefore can not contact the support team – how do we get our account unsuspended?

Thank you