Found this review on Reddit:

Dollar Flight Club has terrible customer service!!!
So last year, I signed up for the premium membership with Dollar Flight Club. I never used it because I found better deals on FREE sites.

About a month ago, they sent me a customer appreciation email. At the very bottom, they reminded me that my membership will auto-renew in 30 days. I didn't see that part because it was no where in the title of the email about an auto-renew date, and the details were at the very bottom. I cancelled on the renewal date. They charged me anyway. When I emailed them, they refused to refund it. Again, I NEVER USED THE SERVICE, and let them know that I wanted to cancel because it wasnt a benefit.They were rude in emails about how they won't refund me. Garbage service for a small company.

This is a warning to either look for better deals elsewhere or put a reminder in your calendar to cancel at least a few days before the auto-renew.

Truly, their deals can be found elsewhere and often times cheaper on other sites. Do your research.