cycle day 41

This is the second cycle in a row to go over 40 days. I'm only 29 (30 in may). No tests have been able to tell why this keeps happening. I know I ovulate on time thanks to CB ovulation test kit. So why can't I just start a new cycle?? I want to try again so bad, but I can't if I don't start a new cycle! I'm starting to get very frustrated and worried. Does this happen to anyone else? Any input would be appreciated!