Changing the size of an existing package (for example 50 GB → 20 GB, or more ports) is done by a manager in chat, not by cancelling the subscription.
Do not use About → Cancel. Cancel stops the package. A downgrade keeps you on a smaller plan.
What to do
Open chat and say you want to upgrade or downgrade (not cancel).
Name the package and the new size (GB, ports, or plan).
A manager will take the request and apply the new size and price.
Self-serve cancel in the dashboard is only for ending a package. See How do I cancel my subscription?.
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