I had the same problem with my pump until I looked at it closely. It actually has two threaded pieces on the nozzle. Separate the two and it will become obvious how to prevent air from escaping the shock. It took me while to figure it out. I ride 75% on road 25% off.....107KG...200ish psi in rear...100ish psi for fork. That is just my first attempt at a setup, so far so good but I assure I will weak it as I gain more experience.