cut and fill toposurface revit vs autocad

[meslija]

Hi,
I created a toposurface in Revit Structure.
I exported in Autocad to see the volume of cut and fill, but the results are different from what Revit Structure gave.
In my opinion the results should be the same.
I need advice to solve this problem.
Thank you

[Organic]

How large is the site and how different are the results?

[meslija]

the site is around 50000m2
revit fill 68m3
revit cut 780 m3

autocad fill 163m3
autocad cut 566m3