These are classes that have fields, getting and setting methods for the fields, and nothing else. Such classes are dumb data holders and are almost certainly being manipulated in far too much detail by other classes. In early stages these classes may have public fields. If so, you should immediately apply Encapsulate Field before anyone notices. If you have collection fields, check to see whether they are properly encapsulated and apply Encapsulate Collection if they aren't. Use Remove Setting Method on any field that should not be changed.
Look for where these getting and setting methods are used by other classes. Try to use Move Method to move behavior into the data class. If you can't move a whole method, use Extract Method to create a method that can be moved. After a while you can start using Hide Method on the getters and setters.
Data classes are like children. They are okay as a starting point, but to participate as a grownup object, they need to take some responsibility.