Zanussi washing machine stops half way through cycle - no error code?

Zanussi washer dryer ZWD16270W. It stops half way through the cycle. There is no error code displayed the timer just goes back to show the full length of the cycle. The machine will not then start again, when you try the machine makes a noise like it is going to start but then clicks the door lock open. If you leave it for a few hours or until the next day it will start again and sometimes it will complete the cycle!!

Thank You!!