Reclaiming income tax from bonus clawback

When I moved jobs I had to pay back the net amount of a bonus I had been taxed on to my old employer. I was given a sig on bonus by my new company with which to pay it, and hence paid tax on this sign on bonus. I have therefore paid tax twice - how do I reclaim one of the income tax/NI charges?

Hi,
We are unable to answer queries relating to issues with personal records.
Please contact HMRC Personal Taxes Helpline on 0300 200 3300.
Thankyou.