Jason1wood it sounds like the autofill solenoid is leaking to the service boiler (steam boiler). Normally the solenoid is normally open to the brew boiler, and when the service boiler requires filling puls in and opens the way to the service boiler. When it does this it will try to fill service boiler and you’re unlikely to get much flow out of the group, if any.
The high pressure in the steam boiler is probably because that boiler is now over full or filling and the pump is pressurising the boiler, pushing the gauge around as far as it will possibly go. I would imagine that if you open the top you would probably see water coming out of the safety valve, if you carry on.
It could be a simple as a scaled level probe, or a loose wire on the level probe, or a broken wire or bad connection to the Gicar box from the level probe.
Usually the symptom of this is when you turn the machine on the pump runs and tries to fill the steam boiler. If however, it doesn’t do that, and only does it when you raise the lever and then no water comes from the group while it seems to fill the steam boiler, then the problem is a different one, because for some reason the solenoid is open or opening to the steam boiler when you lift the lever. Could you confirm exactly what’s happening, or what you think is happening..