[Hummingbird] Performance test not running

Hello,

I'm trying to run a performance test with Hummingbird but it keeps coming up with the following notice:

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,

Kind regards,
Amber