How to disconnect a website from WPMUDev without access to the website ?

Hello,

When I go to my WPMUDev homepage I can see the list of all connected website. On that list there is a website called "[REDACTED - Please let me know if you need the name, don't want it to appear on Google". I want to disconnect that website from my WPMUDev.

The problem is, that website belong to an ex customer of mine that was very dishonnest. After we had a fall back they changed the password to the website, so I cannot access it to disconnect and/or remove WPMUDev manually.

I tried many time to use the "Remove website" function in the "https://premium.wpmudev.org/hub/my-websites/" area, but each time it seems the website is reappearing after a while ?

So my question is : given the fact I cannot access the website's admin anymore, how can I permanently disconnect that website from my hub, since the "Remove website" function doesn't seem to work ?

Please let me know. That customer was very dishonnest to me, so I feel they don't deserve to have access to MY WPMUDev licence, and I don't want their website to use ressource on my account.

Please let me know, thanks.