Nighthawk CAX80-100NAS cable modem router doesn't see External HD Apricorn FIPS 140-2

I am trying to connect an external hard drive Apricorn FIPS 140-2 to the Nighthawk CAX80 cable modem router using the USB 3.0 port at the back of the Nighhawk but the light at the front of the modem router doesnt lit.

I have logged in the gateway and the ReadySHARE Status shows No USB Drive. Attemps to ReadyShare from my laptop only shows connection failed messages.  

I connected the Apricorn to my MacBook Pro and able to see the HD and back it up with Time Machine.

My ISP is Xfinity.  Question is if the model of this hard drive is compatible with the model of the Nighthawk.

Any input will be greatly appreciated.