Uncircumcised cocks and condoms please help?!?!

Recently I became single after a 5 year relationship. My ex was circumcised. One of the guys I've been fucking is uncircumcised and I love it. He is huge and knows how to use it. I have the mirena IUD. He told me that he can't use condoms because they come off and pinch his foreskin. Is this true or is he just saying that so he doesn't have to wear one???? Any advice would be great!!!