Flow Smart Overheating at low RPM and High Power

I've had my Flow for a few months now and its generally been fine

However as I've start riding a few more of the hilly Zwift sections I've had on a number of occasions the unit drop all resistance and data.

Cadence is around 68-70rpm and power around 280w

Looking at the Tacx Diagnostic iOS App, its telling me its a temperature issue

Any way to resolve this?