To add, delete or see informations about your subsriptions, go to Settings=> click your Avatar => Subscriptions.
Log in at GlotDojo's homepage => Left click on Avatar => Select Settings to open Account Settings => Select Subscription.
On the Subscription page you can see details of the Pro package purchased.
(1) Expiry date: Usage period of the purchased Add-on
(2) Paygate: The payment method you used
(3) Date of purchase
(4) Devices: the devices that you are using this Add-on on
Note: You can only use the Premium Add-on packages on up to 5 devices at the same time.