Why did someone else's meeting appear under my sign-in?

I received an e-mail from Zoom saying that a new Zoom Sign-in was detected to my Zoom account. As this was unexpected, I launched Zoom (on my Windows 11 PC) and saw a meeting in progress of some professionals going on. I even joined it and then I tried to attract their attention, but could not do so. The meeting lasted 1 hour and 10 minutes. It has left a recording behind, which I cannot delete.

It cannot be that these professionals hacked into my Zoom account to use it! So how did their meeting end up under my account?

Most seriously, there is the confidentiality aspect, that a business meeting should have leaked out in this way.