Moosend has built an internal tool that detects bounce rates and complaint rates to protect users and the infrastructure.
When you exceed any of the bounce and complaint rate thresholds, Moosend automatically blocks your account. You will receive a notification that your account is on hold and you cannot send any further campaigns. You can contact the deliverability team to get assistance about your blocked account.
The deliverability team reviews blocked accounts and investigates why the bounce and complaint thresholds were exceeded. Accounts are reviewed during business hours, Mondays to Fridays, from 6:00 AM to 14:00 PM UTC.
While your blocked account is under review, it is still active, and you can use other Moosend features. However, you cannot send any type of campaign.
Moosend temporarily blocks suspicious accounts and disable sending of campaigns for two main reasons. The first reason is to protect the sending reputation and safety of all Moosend users. If an Internet Service Provider (ISP) detects a high bounce or complaint rate from a particular sender of a Moosend campaign, the ISP can block all other Moosend email campaigns from being sent on their ISP. Second, while accounts are blocked, affected users can clean up their lists and investigate possible issues with their subscription sources. A healthy mailing list guarantees better delivery and deliverability rates.