New Pumper needs help

I just recently got a Vacu-tech pump and I can’t get it to keep it suction. I have shaved around the base of penis and I used Vaseline for added suction. If I keep pumping and and pumping it tends to keep the suction, when I stop it looses suction. What am I doing wrong. Any help for a beginner.

Thanks

Make sure you are not losing the vacuum through the fitting on the top of the tube (do NOT overtighten it though) and that the male fitting connected to the pump hose is securely snapped into the female fitting on the top of the tube.

Plenty of soapy water on the joints will always show the air leaks with lots of bubbles