Unable to Start Session with Ecu

I wanted to upgrade the map in my Stage 2R ST180 and got asked for a read of the ECU.

I flashed the stage 2R myself using the supplied flasher and map so am familiar with the procedure of reading from and writing to the ECU. However now when I try and read the ECU I get the following messages

Ecu Communication Lost
Unable to Start Session with Ecu
Unable to Execute Ecu Reset Command

Up to the error message everything looks fine and it identifies and retrieves the ECU information correctly.

The car behaves as it should and Forscan do not seem to have any issues communicating with the car.

I've visually checked the wiring which looks fine so before I take the ECU out of the engine to inspect to water ingress, etc is there anything else I can do to check for issues?

Cheers