I had the same issue with my Boeing yesterday for takeoff. Engine 3 & 4 not able to start with crtl+e to start engine. It appears that this button combo is only working half of the time lately.At least it still responds somewhat,unlike pressing b to fix a wrong altitude alltimeter…that doesn’t seem to respond at all…
I searched a how to tutuorial on youtube to start engine 3 & 4 on the boeing,since the key combo would only start engine 1 & 2,not 3 & 4.
maybe this guide to start engine on A320neo helps for now if the key combo to start the engine isn’t working properly/not too responsive for you too