ida-x305 Bluetooth Setup Help Needed

I have an Alpine ida-x305 head unit.

I connected an alpine kce-237b cable to the back of the unit which gives me an aux input.

I then connected the kce-237b cable to the AUX out on the NFC bluetooth receiver to allow me to stream music to my head unit through bluetooth.

Problem is, the NFC device is not connecting to the head unit.

The head unit has both AUX IN and AUX+ inputs to choose from. Ive read that the AUX+ input must be turned off to allow the bluetooth to work. But, when I simply connect my phone to the kce-237b aux cable, it will only play music on the aux+ input and NOT the plain aux input. So I think this is where my problem lies.

Any help would be much appreciated.