Moto G7 river Bluetooth call audio with EONON Headunit

I have been struggling to connect my Moto G7 river Eos 1.20T to an EONON headunit for Bluetooth calls.
The phone and EONON car stereo pair successfully and I can see the phonebook on the car stereo.

When I initiate a call on the car stereo it activates the phone dialer on the Moto G7 and shows EONON as the audio output but as soon as the call connects it drops back to the phone speaker.

No audio coming through car speakers and it causes the EONON car Bluetooth to freeze up.

I bought a Moto g32 today and tested and the Bluetooth calling worked straight away.

I think there is something in the Bluetooth audio on Eos that is preventing call audio but cannot figure it out so back on a Google phone after 3 years which I am not enjoying. :sob:

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