This is to inform you that you need to update box 6 with the net gains after deducting any kind of relief that you want to claim. Also, please update the code PRR in box 8 by navigating to Self Assessment >> Client Specific >> Edit return >> Supplementary pages >> Capital gains. Please refer to the below HMRC notes on the same for the tax year 2024-25. Please check from your end and update the box accordingly to get the correct calculations. Once done, you may please refer to the SA 302 computation.
https://assets.publishing.service.gov.uk/media/67e1612564220b68ed6a7009/SA108-Notes-2025.pdf