Remember last month, when a glitch in United Airlines’ booking system allowed people to score cheap (and sometimes free) tickets? Well, it’s happened again.

Mashable was the first to report this new glitch earlier today after a reader noticed that having two tabs going while booking his flight on United.com resulted in the website somehow thinking he had enough miles to cover the entire cost of the flight. The only remaining cost was for taxes and fees — $49.40 — pretty good for a roundtrip flight between New York City and Dublin.

United eventually closed the loophole and tells Mashable that, unlike the September situation, it will not honor these dirt-cheap airfares.

The difference, explains the airline, is that the September screw-up was a result of human error on the part of United, while this is a case of customers “intentionally manipulating our website.”

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