Cannot find DTA S40 via serial/usb connection

Desperate for some help here…

Samsung galaxy tab s connected to DTA S40 via prolific serial cable, plus good quality usb to micro usb otg.

DTA set as per;

Realdash cannot find the ecu in garage connections!

It did once very briefly, first time with a new micro usb otg cable however i unplugged to change water temp settings on the laptop, now nothing, on 3 separate otg cables. On that note, with same cable this connects instantly to the laptop!

I have no idea, tried everything I can think of and this is now one of the last pieces stopping a new rally car build completing, it was meant to be easy, any help much appreciated!