Implementing XFEM in ABAQUS using dynamic implicit step

Is there anybody who has implemented XFEM in ABAQUS using dynamic implicit step? My model runs fine when I use 'static, general' step but when I change it to 'dynamic, implicit' I get following error message"The following XFEM cracks are failing to correctly generate and says crack domain contains invalid element shape." Please let me know what do I need to change in the model to fix this error. 

Thanks so much for your help,

Sincerely,

Vinod Kushvaha