What version of the software is this running? Does it have the latest EGO5 software?
I could probably do the £100 in person to save posting
also - do you think there is a chance its the poppit, as that wouldnt just be an oring...
TBH I have no idea what the fault is, and no time to spend fixing it.
Look at it this way, it's in immaculate condition and comes with a full spares kit which should sort the fault.
If that doesn't, you give it to Robert at Planet and he will fix & service it for £30.
So worst case, you have spent £130 on a very nice gun.
Your choice.