Kate,(posted 7811 days ago)I agree with what Mr Pendle says above, get them to justify their claim and prove they sold your property for a fair price (they have an obligation to do so). See the Home Repo's 'Do's and Don'ts', if necessary issue them with a SARN. I wouldn't be at all surprised to find that they owe you money, as so many properties were undersold. I would also get your local MP involved too.
Good Luck.