By default, the tool is set to Use this setting for standard repairs.
Usually a driver issue or a bad USB cable. Reinstall the VCOM drivers. Alcatel 9015Q Flash File MT6737m 6.0 Tested - Firmware
This means the partition table on the device is different from the file. Change the dropdown menu from "Download Only" to "Firmware Upgrade" . By default, the tool is set to Use