Network | Type 276 Unknown Or Unsupported ((install))

Older RILs (pre-Android 8) may have incomplete enum tables.

Check the thread where you downloaded the ROM. Search for "Network Type 276." You will likely find a flashable ZIP file containing a "fix" or a specific radio/modem image that the developer recommends flashing to correct the mismatch. network type 276 unknown or unsupported