If you subscribed via the website, unfortunately, there is not currently a way for you to change your subscription type. Instead, you will have to unsubscribe from here, then subscribe again, choosing a different package.
If you have a web subscription and want to upgrade your subscription from monthly or quarterly to take advantage of a discount offer on an annual subscription, please purchase your annual subscription through the website, and then contact our Customer Support team to update your account.
If you subscribed on the Apple App Store, you can find more information about how to change your subscription here.
If you subscribed on the Google Play Store, you can find more information about how to change your subscription here.