MESHING FAILED

Hi guys... Im facing this error while meshing my model on PLAXIS 3D?? Could anyone help me??

Thanks in advance

0156> _gotomesh
OK
!!!!> _mesh 0.05 30 15 256
Meshing failed with the following error:
Meshing failed. Check your model for inaccurately snapped objects, or try using different local coarseness.
Bounding box around problem area: (5.641; 3.084; -4.462), (5.771; 3.222; -4.156).