Coupon code feature

Hi,

Today I have received an email with the subject: Review our products to get discount coupon. Even though I turned off the coupon for reviews feature. The content of the letter was:
Thank you for your recent purchase from our company.
We’re excited to count you as a customer. Our goal is always to provide our very best product so that our customers are happy. It’s also our goal to continue improving. That’s why we value your feedback.
Thank you so much for taking the time to provide us feedback and review. This feedback is appreciated and very helpful to us.
Best regards!

What could be the reason for the issue and how can I disable it?

Thank you.