You can view and edit your subscription by logging in to your account at Tiege.com.
The first page you see is your Next Order page.
From there, you would click Manage This Subscription by the Skin Care or TiegeClear System.
Press SWAP at the bottom of the pop up.
Choose a new system or product from the options.
You can choose product size for many items from the pop up.
Click "Swap product" to confirm.