Inform HMRC of Employees taxable benefit changes in the current tax year

I have an employees who left the business at the end of June 2023. He had medical benefit declared in the 2022/23 P11D. How can I inform HMRC that this ended on 30th June this year, so that they doesn't overpay tax, during the remainder of this year. I have completed a P46 for their car benefit to stop. TYhank you

Hi Stuart M,
The individual employees need to speak to our Personal Tax help line on 03002003300 to update their tax record. 
The employee needs to confirm they no longer recieve this benefit in kind. 
Thank you.