I have Tecno CA7 with unknown baseband, I tried several times to repair the imei and baseband, I downloaded the DB from here: https://www.hovatek.com/forum/thread-23177.html for the same build number it failed to write with SN_Write_Tool_v2.1504.00. I downloaded the complete firmware it still failed to write.
it said this on the first DA "ERROR: SATATUS_DA_SELECTION_ERR(0xC0030003)"
and this on the second DA I downloaded here "ERROR: STATUS_BROM_CMD_STARTCMD_FAIL(0xC0060001)"