Upgrade license
You can upgrade / downgrade your license and update the billing details at the User Dashboard.
You should have received the login credentials by email after the purchase and you can always request a new password.
You can also change the plan on your WordPress site where you have the plugin installed, from WP admin -> Shared Files -> Settings -> Account (just click “Change Plan”).
Please note that if you upgrade to a more valuable plan’s lifetime license, the price will be the regular price of the lifetime license unless you have purchased your current license in the last 7 days.