Not Recording GA to midi track, virtual keyboard not working

I recently installed a AKAi MPD226 on my MacBook Pro and ever since I cannot record from Groove Agent onto a midi track. Also the virtual keyboard is not working. I have checked the track inputs and all the settings in preferences. I also done a complete reinstall of Cubase but is. still the same. I also installed. the latest OS (just in case). This is driving me mad and would be grateful for any help?
I am running Cubase Artist 8.5.