It is impossible to create a surface on curves

Hello, I created a web of curves and I try to execute “Surface from network of curves”, but I receive every time:

A requirement for NetworkSrf:

“All curves in one direction must cross all curves in the other direction and cannot cross each other.”

Your set of curves has curves in the same direction intersecting.

One way to make you shape would be to create four flat surfaces and fillet the edges.

Another way is to create a box. Explode the box and delete the unwanted surfaces. Join the surfaces. FilletEdge for the rounded edges.

Or create a box and use ExtractSrf to separate the unwanted surfaces from the box and then delete them. FilletEdge for the rounded edges.