Windows 10: Can't login to computer and can't reset bitlocker

My parents recently bought a new home which included all the furniture. This included the old computer and the previous owner claimed he wiped the computer and left it new for them however he appears to have installed it with bitlocker and we can't do anything with it. They have no way to get into contact with the old owner.

I tried having them format it and boot into safe mode however nothing seems to be working due to bitlocker. One of the screens mentions unlocking the drive via the bitlocker recovery key (picture C) which we do seem to have (picture B) however whenever we get to this screen the keyboard and mouse won't work so we can't select to manually input the screen.

Can anybody offer any advice on what to do from here? I'd hate to have to throw the computer away when it would work fine for their purposes. Thanks.

:)

 

AT&T Lumia 1520 bitlocker issue

I have AT&T Lumia 1520 RM-940 in my hand but an issue with BitLocker. I twice tried to hard reset and flash / wipe out all data but when I reboot, display screen says bit locker. I have no choice but to avoid my Lumia. Windows Device Recovery Tool didn't work
on my device as well.

 

Volume Mute Light won´t change color

Which steps did you perform? Was this from a clean boot?
Open administrative command prompt and type or copy and paste this command: shutdown /r /o /f /t 00
It will boot to the recovery options or windows advanced troubleshooting menu.
Click troubleshooting and click reset this computer. You will be saving files. Applications and programs will be removed. Windows will be reinstalled.
Enter your windows logon password.
You will see getting things ready with rotating dots.
Click resetting this PC.
It will then display the HP logo with resetting this PC with rotating dots and a percentage.

 

Manage Bitlocker

At Window ¨Start¨ enter encryption and select ¨Manage Bitlocker¨ option doesn´t exist in list subsequently can´t turn on Bitlocker. OMG, why must things always being that complicated and not living up to their own expectations. Or haven´t I forgotten to
do my homework?!