Hi
fegeeantonioThank you for your asking. For ZC553KL, there will no longer have any maintenance. Sorry for any inconvenience this may cause. Thank you for your understanding and support.
If you still want to unlock the device unofficially via third party method, please note that unlocking the device or flashing the custom ROM are quite risky, may causing security issues like Widevine Issue, banking app usage issue, or unexpected software issues.