These appeals were about a Failure To Attend, it looks like the DWP have accepted your reasons for not attending and your claim has been referred back to the Assessment Provider, they obviously feel that due to the time involved in the appeals that a new claim form is needed to understand your current limitations.
If you want your claim to continue then you need to complete and return the form.
Gordon
Nothing on this board constitutes legal advice - always consult a professional about specific problems