If this happens, your ability to successfully deliver emails to the inbox of your intended contacts will be compromised and negatively affected. Depending on how severe this is, your mailbox / sending domain may be rendered no longer useful (too much damage to recover the reputation and continue using it). In such a case, you will need to stop using the problem mailbox/domain and begin using an alternative one.
Your best protection against this type of problem is to do all you can to make sure the contact data you use is accurate and reflects a targeted approach. The more targeted and relevant your message is to your intended contacts, the less chance there is that you will run into problems with your sender reputation.
If you do run into issues, you will need to speak to an email reputation expert/consultant who can help you understand and navigate what to do next.
