From your settings, once you log in, you can upgrade your account by following the next steps:
Log in to your account
Go to your 'Settings' in the top right corner of your page
Select 'Change plan'
Choose the subscription that best fits your needs
Once selected, please 'Confirm and upgrade'
You will be redirected to a Stripe page, where you will need to select 'Confirm'
You can confirm your new subscription update on your Settings page