Still unable to enroll, is it too late?

Ok so I got into birkbeck uni through clearing like a month ago and submitted proof of id and other documents. They didn't email me anything for ages and so I rang them up 2 weeks ago. The man said that my application should be processing and to give it 3 days, still no email. I rang up again 5 days later and they said that they didn't get one of the documents which I sent them even though the guy before said everything was fine. So I sent it off and now it is friday, the course starts on monday and I am still not enrolled. I have no clue what to do at this stage and they are busy at the moment on the helpdesk. I dont even think they are open on saturday. Is it too late for me to start the course in time and will I have to take a whole year off because of this?