Information regarding Premium subscriptions and payments

• I didn’t get my Premium code or time on my account
• What should I do after getting an error: “This License Key is already in use?"
• Why am I being asked to pay again?
• Why am I still getting ads/bandwidth limit, I paid for Premium.
• I paid for Premium, but my device says “Account Expired” or “Protection Expired.”
• I paid via Google Play, but my account is expired on Android