Email stillcode@alexshul.com. Please include your device model and OS version.
Sign in to the new iPhone with the same Apple Account, turn on iCloud Keychain, and install Stillcode. Your codes are there.
If they are not, iCloud Keychain is almost always the reason. Check Settings → your name → iCloud → Passwords on both iPhones. The app cannot turn it on for you and cannot tell whether Apple has finished syncing.
Codes stay on the iPhone they were added to. There is no copy anywhere else - not with us, not in iCloud. Add them again on the new iPhone from each service's own settings, or turn on Stillcode Pro before you change phones.
Then the codes are gone, and nobody can restore them - we never had them. Recover each account through the service itself, using the backup or recovery codes it gave you when you set up two-factor authentication. That is the route every service provides for exactly this, and it is the reason they hand you those codes.
The file cannot be opened. It is encrypted with a key derived from the passphrase and the passphrase is not stored anywhere, including on your device. A damaged file and a wrong passphrase give the same message on purpose, because telling them apart would help someone guessing.
Subscriptions are handled by Apple, not by us. Open Settings → your name → Subscriptions on your iPhone or iPad, or System Settings on a Mac. The one-payment option is not a subscription and does not renew.
If you bought Stillcode Pro and the app does not show it as unlocked, tap Restore purchase in Settings. That needs a connection, because it asks the App Store. ⚠️ Without a connection the app keeps whatever unlock it already has rather than removing it.
Email stillcode@alexshul.com with the details. Please do not post it publicly first.