I am looking for advice on my position. I am completely liable for the underpayment? There have been lots of mess ups at both the tax office end and with my employer.

I need some assistance with completing my returns.

I am a full-time employee working for a large (high street name) business.

They have put me on the wrong tax code (basic rate, rather than the higher rate I should have been on) for the last 4 years. They have just realised. I have told the tax office. The latter want me to complete 4 years of self assessments.

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