MICROMAX Q372 PHONE DEAD

[pj7]

I was facing an issue with the phone being stuck in logo screen.I tried to wipe the user data and was unable to do so via recovery.So I flashed the phone with stock rom using Sp Flash tool.Still it once again remained stuck in logo screen.So I tried to format the phone and after that the phone is dead , It does not charge nor power up.I once again tried with format all and download and sp flash tool flashed it successfully and showed the okay screen.The flashing process is happening but the phone does not boot on pressing the power button.It is like totaly dead.Except the only thing that recognizes my phone is the flash tool.Even my laptop which runs on Ubuntu 16.04 does not show any kind of indication on connecting.Please give me a solution.I am very panicked.

How I encountered this problem:
1.Since I was stuck at the boot loop.I tried to wipe data entirely through recovery.There was mount error due to encryption.So my only chance was at flashing the phone.
2.I had 3 version of stock Rom for 3 different build(I didn't know my build no).I tried flashing them all but all the 3 flashed successfully but the result was 
same.Stuck at bootloop.I found out this might be because I was unable to wipe the data from phone.
3.So I wiped the entire data using sp flash tool using the format flash except boot loader option.
4.After that I  had 3 versions of stock Rom with me for different build no.And I think I flashed the one with
the build no which was not meant for my phone.
5.The flashing was successfull.But the phone was dead.
6.Then once again I reflashed other version during which once the flashing was interrupted.
7.Finally I flashed the correct Stock rom version for my build no.Because It was in the end I found out my build no.  
8.The flashing was successfull except the phone is still dead.

Observations:
A.Memory Test: 
      1.ERROR:NAND FLASH NOT DETECTED.(This was present even before the phone became dead .ie when it was stuck at the boot loop after flashing the firmwares). 
      2.ERROR:UFS not detected.(This was present even before the phone became dead .ie when it was stuck at  the boot loop). 
Rest went well.The memory test in the end showed the okay message.
B.Format option:
Now the format option does not work.
When I try to format the phone once again using sp flashtool format whole flash except bootloader.It says ERROR : S_DL_READ_PT_FAIL (5073).

what went well?
I am able to download the preloader first and then seperately download rest of the components.
This I am able to do with and without the battery.

what didnt go well?
1.The phone is still dead.No reaction from the phone on pressing any button.
2.Phone LED does not blink or light up on connecting with or without battery to the wall charger or laptop.
3.The screen is black.

I have a question.
should I try the format whole flash option and not format whole flash except boot loader?
I did not try this since latest version doesnt have this.And there are many people who have encountered problems too with that option.

PLEASE HELP ME.THANK YOU.