The problem may arise due to low-quality contacts that include a significant number of outdated or incorrect email addresses. This can potentially harm your domain's reputation and have a negative impact on your future email sequences. Therefore, it's important to regularly maintain and update your contact list to ensure that your emails reach the intended recipients and to safeguard your domain's reputation.

We strongly recommend that you validate your contact lists before launching a sequence. You may use our validation service or any other service you prefer:

According to our Usage Policy, we have a minimum requirement for an acceptable email bounce rate. If the sequence reaches an 8% bounce rate per 24 hours, Reply stops sending the first step of the sequence but continues sending its follow-ups. After 24 hours, Reply automatically resumes sending the first-step emails; the bounce rate is reset. Once the bounce rate is reached again, the same logic is applied.

We will notify you of sequences that have reached half or full bounce quota so that you can prevent sequence suspension.

For more details on how to improve your overall email deliverability score, please refer to this article.