Stick hoover Vax blade ultra faulty (Ewshot GU10)

This is about two years old and harldly used BUT for some reason, it will run when charged but NOT for more than about 20=30 seconds, donen't sound overworked running but still will not stay on, probably something to do with a cut off switch, took it to the repai cafe but they couldn;t find the fault, so if anyone wants to have a try, its yours, or for spares