I've spoke to a technician at KEE who advised me a brand new poppet has been installed. Gave me something to try but didn't work.Ive blatantly stolen this from the nation as its easier than typing it all out. Hope this helps.
I'd rather not try taking apart the solenoid and knackering it. I'm pretty good at losing small parts too.
This is something Invert should have done the 1st, 2nd, and 3rd time it went into them.
Hell, there shouldn't have been a 2nd and 3rd time.
Update for the situation though: John @ KEE has promised me a call back from his engineer. But with the rate of call backs to promises of call backs being at 0% so far, I'm not holding out.