Hello lovelyone05, I'm Dr. Steve Mahannahan.
I have read into your question and I've come up with the logical answer.
There are many factors in why a man will not experience an orgasm during sex, however, the most occurant reason for this is because the man you are having intercourse with is actually a woman. Most people assume if it has a face it's a guy, but this is common misconception. Check the genetalia, if you aren't sure, check again. -Dr. Steve