I am disappointed to find that the Serfas website has NO instructions for their pumps or other products, as if it is intuitive for a novice to operate them.
As a customer you should contact them and complain.
Do you have the connection to the tire valve tight? You must have the connector pushed completely down and the locking lever pushed in the down position. Be sure it can not be pulled off of the valve while pumping up the tire.
Fixya is a place to ask people questions, not to obtain things directly. Usually the best thing to do first is search Google, but I could not find a manual for your computer that way, so I'd suggest you contact Serfas: https://www.serfas.com/contact-us I’m happy to help further over the phone at https://www.6ya.com/expert/donald_f2ed37026a3ac881
generally you have to put the pump up to the nozzle and have the lever down then put the nozzle in tightly and then pull the lever up. If after several attempts it doesn't work the pump may be broken, as bike pumps generally break easy
