Delete entry from dashboard

Hi, I added resuts of the growatt (solar panels) to the dashboard but I accidently chose the login from my previous house and panels (which I do not own anymore). Apparently, the buyers did not change the login. (I now also own a growatt but the login I thougth was correct is that of my old house). How can I delete the entry in my dashboard without affecting anything with their growatt?
thanks!