Income from ex-employer before moving to UK

I worked for my ex-employer up to January 2023. And I moved to UK in March 2023. Recently I received a small amount of money from my ex-employer. This income is the adjustment to my salary for Year 2018-2023 ( before I moving to UK and becoming tax residence) because of mis-calculation of their payroll system. Should this income counted for the current financial year?

Hi,
No.  
It is income arising from employment when you were not UK resident.
Thank you.