A：1. When using certain third-party applications, the touchscreen may be unresponsive. Ensure your device's ROM is updated to the latest version and try updating the third-party applications to the latest version as well. Additionally, some third-party applications have design flaws that create the illusion of touchscreen insensitivity.
2. If your device supports glove mode, check if it's enabled. In glove mode, touchscreen sensitivity is greatly increased, which may cause the screen to become overly sensitive, resulting in random flickering. It's recommended to disable glove mode when using the device without gloves.
3. If the screen becomes blurry when using certain applications, it's generally due to incompatibility between the application and the device's system or hardware. Please ensure the application's operating conditions are compatible with your device.
4. If the problem persists after the above steps, it may be a hardware issue with the touchscreen. Please back up your data before having it repaired.