Errors in FRANC3D software

Hello to all,

My project is crack propagation in expander wheel.

I did static analysis in abaqus and i used FRANC3D for crack modelling.

I insert crack in FRANC3D, surface meshing is done but not volume meshing.

It gave me this error:

backtracking stagnating: restarting contraction

What is this error?

Can anyone help me?

I attach 2 pictures. First picture shows the meshing and another shows crack location.

In crack location i have two seed size of elements because of model geometry.

What is the reason for this error?

thanks to all