Ob-Gyn questions? Ask a gynecologist online.
Yes, sometimes the sperm can't penetrate the cervical mucous or into the egg. In this case the reproductive endocrinologist would recommend injection of the sperm directly into the uterus or into the egg.
If you are not yet seeing a reproductive endocrinologist, it's time to see one. If already seeing one, this would be the next step in evaluation as per the link.