Periodic mesh in gmsh

Hi,
I create the geometry file .stp by using CATIA and i import it to gmsh.
when i set the function periodic surface in order to have similar meshes :

boundS13[] = Boundary{Surface {13};};
boundS17[] = Boundary{Surface {17};};
Periodic Surface 17 {boundS17[]} = 13 {boundS13[]};

i get this errors :

Could you please help me.

Have you asked Gmsh people?

I can’t find the community of gmsh