You can cancel your League of Traders account through your Settings page.
App:
Profile → Settings⚙️ → Account → Delete Account
Web:
Open your account menu in the top right corner → Settings → Delete Account
Make sure you understand the following before deleting your account:
Deleting your League of Traders account means that your portfolio data and any paid subscriptions, such as PRO subscriptions, will be erased and cannot be retrieved.
Your personal information will also be deleted per the League of Traders Privacy Policy.