E5573Cs-322 Dead only red light appears when power on it or insert usb cable help

[gsmcity828]

History,
customer flashed it with wrong firmware and after that took it to me....
FW Version installed before flashed is 21.327.62.00.1456
Fault,
only red indicator light appears when power on it or insert usb cable.s
it makes "3G PC UI Interface" port with short point.

i tried 2 FW downloaded from dc support but showing errors during flash, see below

2020-02-12 01:21:45 PM Starting repair device...
File to write: USBLOADERFILE
Looking for attached port...
Preparing to write...
Writing file 1 of 2...
Writing file 2 of 2...
Error downloading file 1 of 1
Error writing software
2020-02-12 01:22:08 PM Unlocking device finished with ERROR

Huawei_E5573_Firmware_21.328.62.00.738_SIGNVER.dgt ks
Huawei_E5573_Firmware_21.329.62.00.1217_SIGNVER.dg tks

now what i can do more to alive it?

[Valdemaras]

Signatures do not match, won't be possible to repair this version.