Keyboard problem. extra letter when typing, not a windows 10 issue

my problem is this… my laptop motherboard burn… so i order one from aliexpress.
the laptop is working with the mother boart i order but i have a problem with the keyboard.
when i press number 7 it write 74 if i keep pressing it write 44444
if i press 4 it write 74 and if i keep pressing it write 444444

and so on with other keys g =gt and keep pressing it is ttttttttttttt
if i press h = hy and if i keep pressing it is yyyyyy

i have remove the keybord and i manualy short the pins on motherboard to see if the problem is in my keyboard… the problem is not my keyboard, it o the same thinks

so i wondering if the problem is the bios… or the motheroard he send me is no good.

the bios version is 7wcn38ww
mtm is invalid
lenovo sn is invalid
uuid number is there.

do you think my prolem is in bios?// or is a hardwear malfuction

bad think like idiod i throw away the original matherboard. i could replace the original chip and find if the problem was the bios…
bad think no2 the idiots to lenovo service for some reasson delete all the infos in the back of my laptop, i dont know why… maybe they but other persons laptop back cover or they did it in purpose…

Missing serial and other machine specific information is expected to be missing, could possibly get restored from old board / spi.

Otherwise dump your firmware and compare the static parts to the stock bios.

Keyboard is normally connected to EC which has its own firmware.

Does an external keyboard (USB) work OK?

yes external (usb) keyboard is working fine…

unfortunattly i dont have the old motherboard, like a stubit i throwed away…