If the emails are being delivered to the server in the SPAM/BULK mail folders, you will need to contact that particular ESP (email service provider) for assistance. Our scope of support only covers and guarantees that the emails will be delivered to the server not how the server will handle them afterwards. This is due to the fact that there are a number of factors that go into how emails are flagged/categorized and, unfortunately, the only part of that we can control is the IP address the emails are sent from. Since the emails are hitting the server and are indeed being delivered to the address, our support stops there.
Following are the most common ESP links for ensuring prioritized delivery: