Humming Bird Test not Running

Humming bird isn't working. It keeps saying that it cannot generate a report. It says the folowing:
"The performance test didn't return any results. This probably means you're on a local website (which we can't scan) or something went wrong trying to access WPMU DEV. Try again and if this error continues to appear please open a ticket with our support heroes"

Please advise.

Thank you,
- Aubrey