Hi, I recently finished a fixed term contract, but was paid for another 6 weeks. The LA has now asked for the money back - luckily I stuck it in savings, but HMRC are now claiming that I have underpaid tax for this year. I have been asked to pay the amount after tax back, so surely I will have overpaid if anything? Have tried ringing tax office several times - but have been unable to get through. Any advice would be appreciated.