'The disk you inserted was not readable by this computer' when connecting to TV

Hi,

I am trying to connect my Macbook to my TV via HDMI, so I can use Zwift on the big screen. I have purchased a HDMI/USB convertor, but I keep getting a message on my Mac saying 'The disk you inserted was not readable by this computer.' and no display on TV.

Can I been sold a dud convertor?

Any help aprreciaed