Most issues are tied to Google Play or users actions, please be sure to read all the following points.
If you still have issues contact support with your orderId and details about all the known problems (Can be retrieved from Google Payments)
Known problems
Purchase issues
Play Store issues
• Card issues. Not all credit cards works with Google Play and some banks that require user validation in banking apps can fail. You can try another card or paypal purchase
• You need to have data sync enabled for the Google account you made the purchase. (Android settings / Accounts / Google / App data sync)
• Play Store bug can be solved by enabling then disabling the Biometric authentication settings (Or the other way around if you use that option)
• The Play Store needs your phone to have a correct date, time and time zone. Be sure to have those set correctly. A simple way to force fix this, is to force set a wrong date and time then set the proper ones agains.
• You need to have an up to date Play Store version on your device. On many Chinese phone the Play Store version is 2 years old and no more supported by Google libraries. You can easily update from https://www.apkmirror.com/apk/google-inc/google-play-store/
• 您需要在您的设备上安装最新版本的Play商店。在许多中国手机上，Play商店的版本已经有2年之久，并且不再受到Google库的支持。您可以轻松地从https://www.apkmirror.com/apk/google-inc/google-play-store/ 进行更新。
Alternate solution
If you can’t purchase via Play Store in your country, or can’t get your credit card to work via Play Store you can read How can I pay for symfonium without google play? - #2 by Tolriq for an alternate solution.
License issues
Multiple Google accounts
• If you have multiple accounts on your device, it’s important to install Symfonium with the account associated with the in-app purchase. To ensure this, you can uninstall Symfonium from your device and then reinstall it from the Google Play Store website on a computer, while logged in with the correct account.
Lucky Patcher
• Lucky Patcher breaks Play Store licenses checks, which can affect Symfonium’s in-app purchase validation. If you encounter issues with the in-app purchase, make sure to disable all In-App emulation functions within Lucky Patcher. Please note that simply uninstalling Lucky Patcher is not enough to fix the issue.
Ad blocker / Internet access
• Please note that Symfonium performs a license check over the internet on a regular basis when launched. However, if you are using Ad Block Plus, it might prevent this check from working properly. In such cases, you will need to disable Ad Block Plus temporarily to allow Symfonium to validate its license once again.
• Another possible reason for license validation issues could be that Symfonium does not have internet access or it is blocked by a firewall or other security tools. To resolve this, please ensure that Symfonium has unrestricted internet access and is able to connect to genimee.com domain over HTTPS. Check if any other security tools or firewall are blocking the connection. You can check in a browser the url: https://genimee.com/test that should show an OK.
Play Store issues
• If you have just purchased Unlocker via the In-App option, it can take a couple of hours to be available on all your devices. This is due to how Google replicate and validate the licenses over multiple devices. Just wait a little time. If you go to the buy screen and validate that it says already purchased then reboot the device.
• You need to have data sync enabled for the Google account you made the purchase. (Android settings / Accounts / Google / App data sync)
• Play Store bug can be solved by enabling then disabling the Biometric authentication settings (Or the other way around if you use that option)
• The Play Store needs your phone to have a correct date, time and time zone. Be sure to have those set correctly. A simple way to force fix this, is to force set a wrong date and time then set the proper ones agains.
• You need to have an up to date Play Store version on your device. On many Chinese phone the Play Store version is 2 years old and no more supported by Google libraries. You can easily update from https://www.apkmirror.com/apk/google-inc/google-play-store/
• 您需要在您的设备上安装最新版本的Play商店。在许多中国手机上，Play商店的版本已经有2年之久，并且不再受到Google库的支持。您可以轻松地从https://www.apkmirror.com/apk/google-inc/google-play-store/ 进行更新。
Backup restoration
• If you restore a backup (from Titanium or other tools) that includes Symfonium, license information may be incorrectly detected as an attempted license hack. This will require license validation, which can take some time. To avoid this, it is recommended that you re-install Symfonium from the Play Store each time. If you need to re-install Symfonium, be sure to export its data first from the settings menu (this feature may not be available yet).
Note
No solution did work, or you do not understand some points
Be sure to have properly read and applied all the points of the FAQ (multiple times if unsure), then please contact me for help with:
• Your Order Number (listed at Google Payments) or your trial ID and Ko-fi user name if you used that method.
• Logs (Debug logs). To have more details when gathering logs, please click on the purchase Unlocker again to get the error message or the restore license!
• Your details or questions about each of the FAQ points.
Support will not be able to help without all those information.
Remarks
• You can access your order history at Google Payments if you have lost the purchasing email.
• Licenses purchased on Google Play Store are tied to your Google account, so will work on any device using the same account.
• Licenses purchased on Google Play Store are tied to your Google Account and Google does not offer any mechanism to migrate your license to another account.
• Licenses purchased on Google Play Store are tied to your Google Account and will not function on devices without Google Play and that account.