I'm not going to let my sister use my amazon prime account
Is it because you don't want her to see your information?
Yes, I just don't want her to access my account
She should get her own account if she needs it. No one should expect you to share your account.
I told her that but she is persistent and continues to access my account. I think I will just cancel my account so if I go down, I'll take her with me.
That might be a smart move because you can then sign up again, but she would not know about it and you have a good excuse to tell her to make her own account.