his dick stopped working????

Okay soooo i was with my man and i was planning on spending the day with him. we were watching movies for about 2 hours then started to get into foreplay. his dick was hard the entire 45 minutes of foreplay but as soon as i get the condom on and he goes to stick it in he goes limp. this happened twice 🤦🏽‍♀️🤦🏽‍♀️ idk if i did something wrong or like what do i do i need help .