Ravi checked the settings: Settings → About tablet → Status → IMEI information . Both IMEI slots showed and “0” .
Without IMEI numbers, the tablet’s cellular modem was useless. The student had no backup of the original NVRAM or modem partitions. Ravi explained: “The Lenovo TB-8504X runs on a MediaTek chipset (MT8167 or similar). Your flash overwrote the NVRAM partition where the unique IMEI numbers, Wi-Fi MAC, and Bluetooth addresses are stored. The tablet didn’t lose the hardware – it just lost its ID card.” lenovo tb-8504x imei repair
The student panicked. “Do I need a new motherboard?” Ravi checked the settings: Settings → About tablet