Regarding the charge for Kindle Unlimited=, the best way to handle that problem would have been to log in to your Amazon account at www.amazon.com.au/, select YOUR ACCOUNT and then YOUR KINDLE UNLIMITED ( or go directly to https://www.amazon.com.au/kindle-dbs/ku) and cancel the Kindle Unlimited Account from there. Because you blocked the charge with your credit card company this may have affected your billing status for everything billed by Amazon.
Your password ***** your Kindle account your Kindle devices and reading apps should be the same as the password ***** your Amazon account. If you are unsure what your password ***** please go to www.amazon.com.au and click on FORGOT YOUR PASSWORD. on the next screen, enter the email address associated with your Amazon account. Follow the instructions on the screen to reset your Amazon password ***** then use that same password ***** register your Kindle or access your Kindle reading APP.
If for any reason you are unable to login and need help sorting this out you can contact someone who can help you via phone by calling Freephone 1800 064 122 within Australia, or 0800 453 249 within New Zealand. If you can provide enough personal info (including full name on account, billing address, and possibly billing info) they can help you with regaining access to your account, and sorting out any billing issues.
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