All the details are here.
https://www.ebay.co.uk/help/account/changing-account-settings/closing-account?id=4199&st=3&pos=1&que...
You will need to go through the process for each account.
You have recent purchases on this account so you may want to wait before you close it in case you have issues with your purchases.
"There are two ways to be fooled. One is to believe what isn't true; the other is to refuse to believe what is true.”
Søren Kierkegaard, Danish philosopher (1813 - 1855)
