You can cancel a subscription yourself, at any time, in the same medium you used to subscribe: the billing section of the dashboard, in a few clicks, with no phone call, no retention interview, and no email required. Cancellation takes effect at the end of the current billing period, and the plan keeps working until then.
Free trials, where offered, convert to a paid term only after the trial length and price have been disclosed to you, and can be cancelled before conversion by the same route.
Fees already paid are not refunded except where the law requires it or where we failed to provide the service. EU consumers have a statutory 14-day right of withdrawal for digital services; requesting immediate provisioning - which is what creating a database does - means you accept that the right lapses once the service has been fully performed.
Deleting a project destroys its database cell and, on the retention schedule of your plan, its backups. Export first: see Data portability and exit.