I have a ZTE Blade V7 Lite, which is stuck in Meta Mode. If I reboot, I can enter Recovery Mode, where I can select some options, e.g. wipe data, but when I select "reboot", it goes Meta Mode (displays "META MODE" in the corner, and no move).
In Meta Mode, I can connect it with ADB, but I can't do anything, because it's unauthorized:
$ adb devices List of devices attached 10799213 unauthorized
I just wanted to boot into the normal mode (by using some ADB command) and use the device. It came out after a normal reboot. I've already performed factory reset, but still boots into Meta Mode.