Pressure washer (works but faulty) (Hale WA15)

It works as long as the trigger as held.
If the motor is on but the trigger isn't pressed the motor doesn't cut out and water leaks from the handle.

Basically you just need to turn the motor off when you don't want to use it rather than letting go of the trigger

It may be a new trigger or it may be something internal.
It may be an easy fix for someone

Please let me know when you can collect as I'd like it going ASAP