Help with Nipple and Clit pump

Hello! So the crystal clear nipple and clitoris pump arrived yesterday and we were having a little play this morning... The first 2 pumps were great and had the desired effect, however after that the bulb seemed to be allowing air back in as opposed to sucking it from the cylinder. The cylinder was probably 1/3 full at the most so plenty of space left still, we used plenty of lube as suggested so are unsure if it was us or the pump? If anyone has any suggestions that would be great as we love the pussy pump we already have and would love this to have the same effect. Thank you in advance!

Hi.

did you have the same problem on both your nipples and clit?

What sort of lube did you use ? I think the thicker the better. Maybe try a different type. Also try pumping slowly rather than quick pumps. If your still having problems then give customer care a message. They are super helpful.

good luck