Error flashing mi9 cepheus ???

Error flashing mi 9 cepheus
Flash firmware
The bootloader of the device is locked, unable to flash
Finished at local time: [06.27.19 09:42:47]
WorkID: 64124678

and test point edl mode

Downloading firmware
Selected firmware: Mi 9 V10.2.25.0.PFACNXM [fastboot]
Download finished.
Extracting firmware
Processing XML files
Preparing Qualcomm programmer
Gathering device info
Downloading Qualcomm programmer
Connecting to Qualcomm programmer
failed to send sig
Failed to prepare Qualcomm programmer
Finished at local time: [06.27.19 10:59:18]
WorkID: 64128197