Since you already know how to get an orgasm, it should be relatively easy to fix.
The chances are very close to 100% that you orgasm from rubbing your clitoris. That is normal. Your sex organ is your clitoris, not your vagina. Your vagina is your birth canal, an exit point for menstrual flow and an entry point for semen/sperm. As far as pleasure goes, your clitoris is what gives it.
So rub your clitoris during intercourse, or ask him to do it, or get a small clitoral vibrator. Or get on top of him and grind down to get your clitoris stimulated during intercourse. Grind and rub, lean forwards or backwards, rub forward and backwards instead off going up and down. Do whatever you have to do to get your clitoris stimulated.
Spend more tme with his penis inside your vagina, rather than more time on foreplay. Foreplay is nice and we need it, but research showed that it does not make orgasm moe likely for us - penis in vagina time makes the difference.
Best of luck!