I received an income tax refund which I thought I was not entitled to. I phoned the 0845 number and almost lost the will to live after the number of options etc. and was on for ages (at my expense). I posted the cheque back with a covering letter (at my expense) and have since received a ridiculous form to fill in and return (at my expense).
I wish I had just kept the cheque.
By the way, you may wish to learn from my mistake. I do as much of possible of my banking and building societies online. It is very difficult to work out how much interest you received if you do not have statements. I received gross interest so did not get a statement of tax deduction at the end of the tax year which would have given me the information. I had closed some of the accounts so could not go online to check. In future, I will keep a note whenever I receive interest in case I have to fill in any more ridiculous and inappropriate forms.
There's something to be said for the old passbooks.
Rant over and back to the housework - which I also hate.