ESP8266 and SPI = BME68x error code : -3

[AndySmithers]

I have a NODEMMCU hardware setup with a BME688 that needs to use SPI.
For context, this works perfectly using the standard BME68x Arduino Library.
If I try the Basic example and modify this to use SPI
(if (!envSensor.begin(2,SPI))) : Note that my CS line is GPIO2.
I get error code: -3 which is "sensor not found".

As I say, this hardware works fine with the basic BME68x library so I know I don't have a hardware issue.