I am hoping someone can advise me about dealing with HMRC regarding the underpayment of PAYE from 2005-06. My client has all his tax calculations from HMRC since 2006-07. The 06/07 statement says they will collect £900 of underpaid tax through his new tax code. Having checked all his paper work, this amount has now been collected, as have all other amounts shown on his official P800T statements. He thought he had paid off all these amounts - and indeed he has, until last week he received a new calculation showing there is still nearly £1200 outstanding from prior to 2006-07.
I am looking for an arguement to challange this. I am thinking of saying that as he has never been made aware that this amount was outstanding, as it is not mentioned on any official statements, that it is unfair that he has to repay this amount. After all somewhere along the line it must have been HMRC's fault.
Does anyone have any experience of what works in this situation ?
Any thoughts greatly appreciated.