Stuck at EFI Shell and lost eMMC size

[mr_kaboom]

Hi. I'm new here
I have a tablet from China and it have 32GB in eMMC, running on Windows 10 OS
3 days ago it running out of battery and shut down incorrectly.
After turn on it stucked at EFI shell and show only 4 blkdDevice
I have try "exit" command and it went to BIOS setting. But it stucked at EFI again went I choose "Continue". In Boot Manager there is only "Internal EFI Shell" option.
I have tried boot from an USB with Windows 10 installer and used 2 options: Repair and Reset PC. But it show error again and again. Tried to repair boot or repair mbr --> nothing happened. Tried to use "chkdsk" command but it only check the USB key.
I have tried to install new windows 10, but it show only a Unallocated partition 7,2 GB. So, I can't install Windows 10 because it required 10 GB or more. The Diskpart show disk 0 with only 7,2 GB (and disk 1 there are 7,3 GB - my USB, too)
After that, I have tried to boot from USB with win10 PE, tried to recover lost partition. But it's not worked.
So, Can anybody give me an advise? Please.
Thanks for any response.

 

[mr_kaboom]

Anybody can help me? Please!

 

[mr_kaboom]

2 weeks and nobody response

 

[Cardinal_1]

2 weeks and nobody response

Having similar problems with my Mercer B26t tablet. The boot manager only gives me the windows boot manager and the internal EFI shell options. Yet to wrap my head around wtf...Answer will be appreciated.

 

[mr_kaboom]

2 weeks and nobody response

Having similar problems with my Mercer B26t tablet. The boot manager only gives me the windows boot manager and the internal EFI shell options. Yet to wrap my head around wtf...Answer will be appreciated.

Our tablet brick because of cheap eMMC's bad quality. If your tab is out of warranty, try to dis connect battery for 1-2 hours, and press power key about 5 minutes. Hope this work!!!
With mine, I have sent to the retail in China 3 weeks ago and still wait for the result.