What are my rights as a tenant on appealing an eviction notice in the state of missouri? Also do I need an attorney to do so? I

I was served an eviction notice for the first time ever and paid my rent plus past late fees . The leasing office accepted my rent then paid my rent the next month which is this month and I recieved a letter stating the eviction court date was yesterday and thier is a judgment for past court cost. The leasing agent clearly told me they would work something out on me paying the court cost and that everything was fine and that I didn't have to go to court. Now she is saying the landlord is on an evicting kick and is evicting several people. How is this legal when my rent is all paid up and they told me everything was fine. Also how hard is it to appeal this. How often do appeals win on evictions? I am scared to death any new place will not let me lease now. I have a family of 4.