We moved away from meetup.com thinking our meetups would be destroyed at some point.
When we stopped paying, meetup.com actually "offered" our meetups, including subscriber's list with full name and email, to anyone willing to pay to keep them alive.
We are now out of control with no way to get the userlist cleared. meetup.com support is not responding to support requests.
Thinking of any action that we can take against meetup.com ?
The Meetup docs are quite clear about the default behavior if you leave/step down: https://help.meetup.com/hc/en-us/articles/360002865332-Closi...
The answer you needed was just a quick Google search away: https://www.google.com/search?q=delete+meetup+group, e.g. https://support.google.com/developergroups/answer/7378020?hl... and many other results.
Could Meetup offer up this distinction more clearly in their user docs? Sure. But like I said, the Meetup docs are pretty clear what happens when you follow their instructions.
It's hard not to read OP as "we took an action without doing due diligence to fully understand the consequences of doing so." The point at which you make an assumption like this is the point at which you bear equal responsibility for unfavorable outcomes.
Edit—the UI is actually very clear about this, and has been for at least the last couple of years: "Your members will be given the chance to become the organizer and keep the group running without you."