How to fix Gmail blocking emails after users request a quote and receive marketing emails?

Email marketer from Mailjet recommends providing clear and easy ways for users to unsubscribe from your emails. High unsubscribe rates are better than high complaint rates, as they indicate that users are actively managing their subscriptions rather than marking your emails as spam.

Marketer from Email Geeks advises to move on and try again with new everything if a domain/ip is dead to Google. Keeping in mind the advice about opt in/selling the data.

Email marketer from Reddit suggests reviewing your email marketing strategy to make sure the emails are wanted. If users are requesting a quote, then receiving multiple marketing emails, it is likely that it will be viewed as spam. Ensure you get explicit permission to send other emails.

Email marketer from StackExchange suggests not sending marketing emails from the same IP as transactional emails. This will help protect your transactional email delivery in case there are any problems with your marketing emails.

Email marketer from EmailMarketingForum.example says never send a cold list to a main domain. Use a different domain and IP with a good reputation to send it. They also advise using throttling, otherwise everything is likely to end up in the junk folder.

Marketer from Email Geeks suggests changing the privacy policy to disallow sharing email addresses, set the expectation about additional emails, and perhaps use a separate opt-in checkbox.

Email marketer from Email Marketing Pro advises that offer based lists don't work. People sign up to an offer or to get something, but that doesn't mean they want to be on your marketing list. You need to ensure that people want to be on your list and get value from your marketing.

Email marketer from Email on Acid suggests creating engaging and relevant content that users want to receive. Tailor your emails to match user interests and behavior, and segment your audience to send more targeted messages.

Email marketer from Neil Patel Blog suggests cleaning your email list regularly to remove inactive or invalid email addresses. By removing these addresses it should help reduce the risk of being flagged as spam.

Expert from Email Geeks advises to segregate data, don't share data, and totally segregate domains. They guess the sender is getting endlessly deferred by Google either due to low domain rep or low IP rep (probably domain rep). Also suggests that this kind of stuff doesn't do that great via a platform like SFMC when there's no ongoing connection to subscribers.

Expert from Email Geeks shares that recipients just want the quote and not ongoing mail and Google listens to their users. It’s a tough business model and they’ve never had success getting Google to deliver it.

Expert from Email Geeks shares that if someone gives an email for a quote, even on your site, mailing them multiple times a week seems like a good way to get marked as spam.

Expert from Email Geeks suggests if they ask for a quote and start getting marketing mail, rather than just a quote, they’re going to mark the mail as spam, and are not unusual.

Expert from Email Geeks shares that once someone has done the research and bought their piano they no longer want to hear from any piano brokers, piano affiliates or piano wholesalers.

Expert from Word to the Wise explains that list bombing or form bombing attacks can be mitigated through use of CAPTCHA, or other form validation and authentication.

Expert from Email Geeks says this smells like penny stock/payday loan aggressive co-reg leadgen, where engagement is very diluted, and complaints are typically high.

Expert from Spam Resource explains the importance of explicit consent for sending marketing emails. Sending unsolicited marketing messages, even after a user has requested a quote, can lead to spam complaints and deliverability issues. Always obtain clear consent before sending promotional content.

Expert from Email Geeks advises to not use opens to represent engagement, and change to clicks ASAP. They also suggest that the sender has probably burned the IP and needs to ask SFMC to sell them a new one.

Expert from Email Geeks recommends getting SFMC to cough up the rejection messages, because there will be useful information in them.

Expert from Email Geeks explains that because the sender's privacy policy sells PII to other marketers, 3rd-party sites, affiliates, etc, there is no ongoing relationship with the recipient. The recipients inbox is probably a trainwreck and they’re going to mark everything related as spam. It’s not really a sustainable model.

Documentation from Gmail Help explains that senders should authenticate their email using SPF, DKIM, and DMARC. They should also ensure that their sending domain or IP address isn't listed on any blocklists and that their sending practices align with user expectations.

Documentation from AWS discusses managing bounces, advises that you should be removing these from your list. Amazon SES automatically removes email addresses that hard bounce from your sending list.

Documentation from SparkPost explains that it is crucial to monitor your sender reputation and IP reputation. Use tools like Google Postmaster Tools to track your reputation metrics and identify any issues affecting deliverability.

Documentation from RFC-Editor shares that a valid SPF record is required on all email domains. Ensure you have a valid and correct SPF record.

Documentation from DMARC.org advises that setting up DMARC and ensuring it is setup properly is important. They also share that you should monitor the reports that DMARC generates to look for any problems.

Documentation from Microsoft Learn explains the importance of avoiding deceptive or misleading subject lines and content. Ensure that your email content aligns with the subject line and provides value to the recipient.