I looked into this a bit. If your subscription is inactive you can reactivate it at anytime. If you log into Netflix through an app and you don't have an active subscription because it was canceled normally it will prompt you with something like "Re-activate account" or "Re-activate subscription".
I do want to correct something I said. You said that Netflix doesn't really know it's you. My response was that you gave your dad access but I realize I was wrong about that because people in your own house have access to logged in devices which is allowed normally.
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The difference between authentication (your account) and authorization (your streaming plan) is the first issue here they are separate and for good reason. There actually is a way is a way to delete your account [2]. Even if you don't do this it is automatically deleted after 10 months. Why don't they delete your account when you cancel the subscription?
Think of how annoying it would be if your subscription and account were one in the same, considering your account holds viewer data, watchlists, profiles, etc. Here's some scenarios:
1. Payment fails because you went over the limit on your credit card or it expired.
2. You want to cancel for two months and then reactivate (I knew someone who did this every few months to save money)
3. You change your mind after canceling
4. Canceled by accident
5. Someone else who has access cancels
Why not lock the account?
How do you unlock it? Calling them is time consuming and expensive for everyone. They could require the password to be reentered but many people who share Netflix accounts give out the password as well so that's not really a global solution (I assume you didn't). Maybe a support email? or chat support system? Both are time consuming and also money for them.
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The fault is 40% you, 50% your dad, and 10% Netflix keeping it easy for business reasons.
- You should have told your family that you were canceling Netflix, wouldn't they have bothered you anyway if it suddenly didn't work? (assuming Netflix did wipe everything)
- Your dad should have contacted you when he was prompted. I know mine would if he saw something about a subscription being reactivated.
- You could have changed the password of the account
- You could have invalidated all the existing sessions (assuming he didn't have the password)
- Finally, delete the account as well per their instructions
Those last three are all stated in their FAQ about preventing reactivation of accounts and how to delete your account.
Is it fraud on their part? No, nor is it deception just because they only asked your dad to reactivate a subscription instead of also saying "This will incur costs of $19.99 a month.." I will agree with you they could have automatically invalidated all the sessions when you cancel a subscription but you had options.
Finally you were refunded after contacting them. Did they hassle you? How long did it take? You said "...then Netflix not caring to investigate " was the reason they refunded you quickly. They didn't investigate it because they have good customer service. As a subscription service they want you to be happy and, even if you cancel, you might consider coming back. Starting an investigation for one months fee isn't worth it.
On Hackernews we often discuss services where it's difficult to cancel. There are even some where you have to call like the NY times. This isn't the case for both the Netflix subscription AND the Netflix account. Both can be deleted using the app without interacting with a person.
[1] https://help.netflix.com/en/node/407
[2]https://help.netflix.com/en/node/126558