can’t make him nut??

sooo my bf can’t seem to nut from sex w me

he insists it’s not a big deal but his ex n i are mates (no bad blood or anything) and when they were dating n we talked abt sex with our mans she frequently mentioned being able to make him nut

have tried a multitude of positions, oral, and handies but only time hes nutted around me is when it’s just him beating off

idk if is me or is him or what just wondering if anybody has had similiar experiences?