A：1. After the upgrade is complete, a lot of system resources are needed for initialization, which will take longer than a normal boot. This is normal; please wait patiently for the system initialization to complete (usually more than 10 minutes).
2. If you still cannot enter the system after initialization, please press and hold the power button for about 10 seconds to force restart the device. If it boots normally, it is recommended to continue using the device. If you still cannot enter the system normally after a forced restart, please proceed to the next step.
3. Turn off the device, then press and hold the power button and volume up button simultaneously to enter Recovery mode. Select "Wipe data/factory reset" and follow the prompts to restart.
4. If the above steps do not solve the problem, please download the system firmware and flashing tool, and upgrade the firmware via a wired connection to a computer. Note: Before restoring factory settings or upgrading the system, please ensure that the battery is fully charged. Otherwise, a power outage during the upgrade process may damage the phone and prevent it from turning on.