PAYE National insurance underpayment

Please can I ask for a national insurance underpayment in the 23/24 tax year e.g. not enough NI deducted by the employer. Will completing a self assessment be able to correct this?

Hi Adam89,
No this cannot be recovered via Self Assessment.
You will need to contact the National Insurance helpline on 0300 200 3500, for advice on this matter.
National Insurance: general enquiries
Thank you. 
 

I have called hmrc and they said I have an underpayment of £56.60 for the last year. But they will deduct £280 throughout the year because 20% of that is £56.60. When I asked the man on phone to explain he clearly had no idea himself as he just kept repeating the same thing. I want to pay the underpayment now so it doesnt affect my tax code next year. I don’t understand how underpayment of £56 leads to a deduction of £280. The man gave me a number to call but they don’t take payments through it and I cant find an answer to this anywhere. Please give me a number to call and make this payment

Hi Liba2569
Are you able to advise what the debt relates to so we can advise you of the correct area you need to speak to?
If you are referring to tax credits please call – 0345 300 3900
Or the, pay as you earn taxes line on - 0300 200 3300
Thank you.