Missed details in my self assessment

I need to recall my self assessment to include additional detail. How do I do this please

Hi
If submitted online, you can go back in and amend it.
If sent in paer, you will need to write in with the details for it to be amended.
Thankyou.

For Capital Gains tax if I lived in my house for 20 years and then let it out for 9 years and then sold it, do I quote the value when I bought the house or from when I let it out

Hi,

It is from when you bought it.

Thank you.