Excellent advice. One thing I would add:
5A. Do not use your gmail account password for your Apple ID password. Make it a different, strong password.
Ceste wrote:
My question is did anyone can trace the carrier or iCloud account using the hardware identifier?
No. Anyone who knows the Apple ID email address that you use to log into iCloud and who can guess your Apple ID password can access all of the information that you say has been compromised, UNLESS you also enable 2 factor authentication on your Apple ID account.
Excellent advice. One thing I would add:
5A. Do not use your gmail account password for your Apple ID password. Make it a different, strong password.
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