A question related to AWS and cancellation

[ArataWata]

I tried asking this a while ago, but didn't really get much of a reply to it, anyways.

Let's say that the 12 month free trial is close to it's end and I want to stop the instance or service in order to stop myself from being charged.

Is there anyway to cancel it?

[Sp-24]

Question.

Let's say that the free 12 months is close to running out.

How would I cancel the instance to prevent myself from being charged?
I think you close your account.
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