vokera 24e leak problem

[sproot]

hi just fitted a new pressure release valve it was a bloody nightmare to
tighten up all the way round for outlet pipe to attach ,eventually managed it but now leaking as if I over tightened ? was not leaking until I got to right point, any way to stop pipe constantly dripping ,it gets worse the more I tighten it now.
any help appreciated , bloody stupid design these release valves.