How to fix washing machine - door lock light comes on when door open & won't start?

We've just moved house and plumbed in our machine (Candy 1300 Quick 2 Wash), am pretty sure we've done it right, we know there's water getting to the machine etc. However, when we switch the machine on, the door lock light turns on, even when the door is open, and the machine cycle won't start. Possbily need to reset the machine? But don't know where the reset button is? Thanks