Ideas how to allow etc Gadget to recognise on Mac?

Hello, I'm  looking for some help please?

I own a gadget 2 and the sentinel key, on one of my macbooks the etc gadget is usable and recognises... however on the other macbook i want to use with it, primary button doesn't show up. 

My guess is its a driver maybe needing updating or reinstalling, but not sure where to get one from and which drivers it might be.

Any help would be great!

thank you

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