Just connect with pc and go in the fastboot mode...delete the update by which system.is.strucking....

Flashing Failure and Solution

I.       The firmware has been downgraded but user data is not cleared. As a result, the mobile phone fails to enter into the system.

Upgrading downgraded firmware without clearing the user data may cause the mobile phone to fail to enter into the system. Symptoms are as follows: The mobile phone stays in the Flyme balloon window, M keeps turning or themobile phone restarts repeatedly.

This problem can be solved by performing the following steps:
1.   In the shut down or restart mode of the mobile phone, long press the volume+ button and then long press and power button till the Meizu logo occurs, and then release the two buttons. The mobile phone enters into the upgrade window (in recovery mode).

2.   After the window is displayed, connect the mobile phone to a computer byusing a USB data cable. A portable storage disk labeled Recovery in the shapeof a volume will be identified and displayed.

3.   Paste the firmware to the root directory of the disk.

Note: There is no need to change the file name or extension of the firmware.

4.   Disconnect the mobile phone from the computer. Select System upgrade. Click Starton the bottom right corner of the screen. After the checking of the firmware file is complete, the mobile phone automatically enters into the flashing process.

Tips 1: In the Recovery window, you can move the cursor up and down by using the volume button and confirm the changes by using the power button.

Tips 2: In the Recovery window, byquickly pressing the Volume+ button for five times and the Volume– for five times (or quickly pressing the Volume– button for five times and the Volume+for five times), you can enter Android Easter egg mode where all data of the mobile phone can be erased, Data is precious. You are advised not to erase all data unless required.

5. Several minutes later, you will view the system welcome page. The update is complete.

Pls tell me step by step im not able to do
I havent unlocked bootloader yet
When i put command fast oem unlock
Its ask for unlocking after allow yes its went fail