BQ40Z50 - Change Security Keys 0x0035

Hello,

I am struggling to change security keys. For example if I want to change the security keys for both unseal and full access to (unseal) 1234 5678 and (full access) 9ABC DEFG, I would send the following bytes

44 35 00 34 12 78 56 BC 9A FG DE

But that isn't working. Can someone help me correct it?

Thanks