Since this group is not very active for some time, people start leaving this group.
Lets decide a topic for each week (or for two weeks or for a month) and discuss that topic. We can share our knowledge/experience by this discussions and get peoples attention.
First topic may be "If ad hoc testing can be done more than once?" (Please do not discuss this in this topic. if some people will be in, we can open a new topic and discuss it later)
We can use this topic to decide topics.
Who is in?
And also if you want, add your topic suggestions.