Hi and welcome,
Have you had a read through the FAQ's? here is a part from the step by step guide to help with your query;
'Under the Data Protection Act - the Data Controller has only 40 days to provide this information. If they refuse, or do not furnish you with the full information within 40 days, report them to the information commissioner - Information Commissioners Office – Information Commissioner's Office - for a breach of the Data Protection Act. We also have templated letters to force compliance through the courts - see the Templates Library.'
Even if you have read the FAQ's keep going back and having a look as there is always something helpful you may miss!! This helped me loads when i was doing my claim, along with all the helpfull people on here.
Hope this helps