Nand change failed? Pls help

Hi Guys

I wonder ; ( any help is very appreciated)

i made a deal with a fixmen to upgrade my iPad Air 1 (16gb) to 128 Gb ( nand update) he take my iPad and more than 10 days I’m still waiting, he just wanna give my iPad back with original condition ( no nand change) because as he said due to new updates it comes impossible to write any new nands at air series…

but I believe it’s wrong …

there should be a hint he doesn’t know…

as he said he tried with 32 , 64,128 Gb ( toshiba nands) but result is same …

after soldering new nand ( of course copying from all info from original nand to new nand)

then trying to load iOS from iTunes it’s errored ( even he changed the socket)