I hope they have sorted it out now.
It really isn't helpful when government phone lines are not available, or let you get through and then make you hang on - paying - for ages. Probably an 'efficiency saving' - we pay instead of them. And for the busy lines like tax credit, IHT etc the people phoning are at a difficult time without all that frustration.
http://www.parliament.uk/mps-lords-and-offices/mps/ will give you contact details for your MP if you put your post code in - mine give a phone number, website and webpage. Ask them to help.
Another 'inefficiency' - if one department doesn't work properly someone else has to spend time doing something that shouldn't be their job.