5c First power on

I just got a new 5c. I installed 5 12 TB drives. I’ve powered it on as directed in the manual. It’s now been 20 minutes and all I’ve got is a yellow power led and flashing blue leds along the bottom. The Drobo does not appear on the dashboard. I’m using USB C to USB C connection. How long should this take?

I unplugged the USB C to USB C cable and used the enclosed cable. Now it works…