@prim1951,
Your last update had not appeared on the forum (probably delayed for moderation) when I replied, and so I could not take that new information into account in my previous reply. Unfortunately you are rushing into trying things which no-one here has suggested, nor would recommend (e.g. flashing the laptop BIOS), so from past experience on the forum, I may be wasting time making any further suggestions if you continue to try things on your own.

prim1951 wrote:It is very annoying that the HDD Erase software has set this password but will not now accept it.
You are mistaken. This is nothing to do with HDDErase "not now accept[ing]" the password. Your problem is caused by not following the HDDErase instructions to prevent power failures on your laptop during the Secure Erase process, and the limitations of your laptop BIOS to allow you to re-run HDDErase.
Obviously it's too late for you now but, for the benefit of other readers who may find this thread in future, your issue is well-known, which is why it is specifically mentioned by the writers of HDDErase:
From the file HDDEraseReadMe.txt
*NOTE: For laptop users, please make sure that there is sufficient battery life to run and complete the secure erase procedure. Secure erase may take as long as two hours for larger capacity drives. If power is lost during the secure erase, the drive will be in a locked state, preventing all I/O access.
and in the Revision History of HDDErase for v4.0:
- Added warning message to inform users to run HDDErase from AC power and not the laptop battery.
If you don't want to follow the previous suggestions from
Spildit then there are other options that could be tried, but I won't waste time writing them now in case you've already decided what to do...