I read that post... The HPBR Method is applicable only for limited models and 4540s isn't mention in that list. If you can get me the required version of HPBR for this model it would be a great help.
It's an old post from 2017.
Check this new one from HP Expert
As I mention above I chat with HP today and its history is displayed in the post.
I put a password on my Probook 4540s Bios when I bought it (that was a childish move) and now I forgot it because it was a long time ago. I contact HP support and they surprise me they don't reset the Bios password anymore the only option is to replace the board.
Here is my chat history...