Roav Viva Pro Bluetooth Call issues

Have been issue with my Roav Viva Pro, it has set up fine but seems not to receive calls properly. I’m using it with a Samsung S8, connected via Bluetooth and then the Roav connected to Car Stereo via aux port.

When I receive calls the Roav won’t recognise it and comes straight through to the handset, will only work if I’m called through Alexa App.

Has anyone got any suggestions.