If you want immediate help you need to go to Adobe Support. This is essentially a user to user forum so people help when they can.
I am not a RoboHelp Server user but if it is the same as WebHelp in this respect, old content is not deleted automatically. For WebHelp that doesn't always matter as topics no longer required would not have any links to them and even search should not find them. In the case of WebHelp Pro though, I believe (not sure) new content is merged automatically.
See if that helps you find anything that says to delete old content or not merge it.
Post back if not and I will see if I can get someone else to help.