Sadie
You didn't say which model it was. Its a bit of a guess but you may unlock the door by turning off the mains or unplugging the machine and waoting five minutes.
Try this link (and the link to which it leads):
https://uk.answers.yahoo.com/question/index?qid=20090724053833AAd2mEe
Once you know the model number (call it xxxxxx) you could try a Google search for, say
Beko xxxxxxx unlock door
Anon, March 2015
