Zte GRAND X4 User Manual page 160

Problem
PIN Code
blocked
Phone
crashes,
reboots,
freeze, or
cannot be
powered on
Possible causes
You have entered an
incorrect PIN code three
consecutive times.
Some third-party software is
not compatible with your
phone.
Possible solution
Contact your service
provider. If the service
provider provides the
nano-SIM card's PUK code,
use the PUK code to unlock
the nano-SIM card.
Uninstall the software that
may cause the problem.
Upgrade the phone
software.
Reset the phone to factory
status.
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