Adding public ssh key - "Someone has already added that SSH key"

Trying to add my public ssh key to my account, I receive the message : "Someone has already added that SSH key"

I see that where other people have posted about this, Atlassian has removed details about account names and emails, but I can supply a couple of alternatives.    I did log in using my personal email but there were no keys listed, so it's not that one.   Possibly it's been added on my behalf at a company level, but git clone fatal fails.