If so, is there a trick to connecting the purpose designed pump to the cushion?

I have one on my wheelchair on which I spend my days, and a mattress on the bed. However, re inflating the darn thing is a pain . The company’s YouTube videos make it look dead easy, but a klutz like me finds it anything but. The unit just falls off the pump and it is a devil of a job to securely connect it for inflation.

Any bright ideas would be greatly appreciated.