Please tell us some basic information before asking for help:
Model Name: Zenfone Max (ZC550KL Z010D)
Firmware Version:WW_Phone13.8.26.110.20180110
Rooted or not: Rooted
Frequency of Occurrence: Always
APP Name & APP Version (If your issue relates to the app): Unlock Device Tool
In addition to information above, please also provide as much details as you can, e.g., using scenario, what troubleshooting you've already done, screenshot, etc.
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Unknown error. This may be cause by network issue.