Aqualisa Axis Digital, Lights permanently on but no water ?

Hi, I would be grateful for any help in relation to my Aqualisa Axis Digital exposed pumped shower (model AX8415).

The lights on the control unit are permanently on but the shower is not working - no water coming through when I push the start button and no noise from the pump.

I have tried a couple of things - turning the power off for a couple of minutes to see if it resets when turned back on. Also tried disconnecting the data cable from the pump unit and reconnecting, the unit makes a noise when the cable is reconnected but hasn't resolved this issue.

The shower is around 8-9 years old now so well outside of warranty. Wondering whether a new control unit is needed or whether anyone has any other ideas before I shell out several hundred to Aqualisa for an engineer and parts?