HELP URGENT-Cant create a form, wizard doesnt start

[Sunni sunni]

Hi

I am trying to create a form in a step in my workflow builder.
I add a create form step to the workflow then in the form tab I click on the 
create icon but keep getting the message:

'The container does not contain a suitable
for the form data'

,and it doesnt create.  I've tried creating all sorts of container elements 
in the workflow container but I keep getting this message and the form 
wizard does not start.

If you have any idea what I'm doing wrong please let me know any guidance 
appreciated,

Thanks
sunni