Hi
Thank you for your asking. Kindly refer to our official website for firmware information.
Please provide me your current firmware version
Settings>System>About Phone>Software information
ASUS ZenFone 3 Zoom (ZE553KL) - SupportFor ZE553KL, there is no further update plan. We apologize for any inconvenience caused and your consideration will be very much appreciated. Thank you for your continued support and patronage.