Dell 7470 Bios Password Problem

Hi all. i am wondering if people may give me some insight. i have a bios password dell latitude e7470, and in general, generating a dell code is easy. however in this one, while it accepts the code, it does not unlock anything and once restarted, the lock is back again

ive used a ch341a and soic8 clip to dump i believe a bios, but its only 128kb so unsure, and if people want to direct me what software to use to get the full bios, that would be handy.
ive used the programmer version 1.3 i think (85.5 KB)

i have created another dump with w25q128 this time that generated 16M file

cant upload a 9mb file

What’s maximum password length?
I can decode first 12 symbols only.

im not sure how much sorry. got a bin file patched but it bricked laptop so trying to figure out how to get it back, even re flashing saved bin isnt allowing laptop to boot