OEM unlocking was enabled, or an unofficial firmware was flashed. Fix: Flash the exact stock Firmware ZTE Axon 50 Lite using ResearchDownload with the “Factory Reset” option checked.
The modem partition (NV data) was erased. Fix: Firmware ZTE Axon 50 Lite
: ZTE provides offline download packages which can be installed manually if the online method fails. OEM unlocking was enabled, or an unofficial firmware