Hotpoint WF000 Door Locked But No Light Comes ON?

When I try to start any of the programmes the WASH light comes on but the DOOR LOCK light doesnt even though the door IS locked, this prevents the cycle from starting, when I cancel the programme all lights Inc LOCK light come on, please help, I'm a Mum of 4 and people are setting up base camp part way up my washing pile!!!!!

Thank you x