Hi @Saifur, I am sorry to hear about this.
Are you updating your phone using the phone settings (OTA) or are you trying to perform the update using a computer? If the update fails to be copleted OTA, I suggest that you try to update your phone using a computer and Xperia Companion.
If the phone fails to be updated both OTA and in Xperia Companion I suggest that you try to repair the software in your phone, this as a software repair will automaticly install the latest software available. Please note though that a software repair will erase all user data from your phone so make sure to do a backup of your user data before proceeding with the repair in order to prevent data loss.
Try this and let me know how it goes!
