Non active Executive Committee members

What is the ruling on non-active committee members. We had a new election in September, and got a mostly new committee of 7 members — 24 lots in the complex. It was stressed don’t come on the committee unless you are going to participate and do the voting as needed. Only 3 months into the new committee and we have lost 1 member who has just sold, a chairperson who sometimes responds to requests for action, and 1 other member who answers the emails. The rest really don’t bother. Makes it hard to get action happening in the timeframe required for some matters. How can you move on inactive committee members? Have tried to get them involved by door knocking and also personally asking their answer to urgent matters. Was the problem with the previous committee as well, only 1person really did anything.