I’ve had this pump for a couple of years, only used it a couple of times.

I came to use it last night, but found its got some kind of air-lock as even when not attached to valve, when I pull out the handle, when I let go, it sucks the handle back down.

It does this regardless of whether lever is up or down.

I suspect it was fine before I lent it to someone on a group ride 🙁

is it kaput?

I har this happen with a pocket rocket. Used it once. Less than 2 months old. Came to use it and it was air locked. Pretty poor really. I should get round to sending it back to wiggle.

Valve stuck shut mine stuck open so soon as you connected it to the tyre the handle shot out. Complete strip and clean is needed.