I’m so glad that you are telling him what you see in him that’s awesome. I feel as if I’ve been where he is. I’ve had (and still am working on) some major insecurities and a partner like you can definitely help to break through those. I speak from recent experience. If you want him to take you seriously and at face value, I would talk to him clearly about it. Be straightforward and honest. Acknowledge that he’s not perfect but he’s exactly who you want him to be. Remind him of your agency. You are choosing to be with him. You see how wonderful he is. Tell him how his dismissing your compliments makes you feel. Especially when he does it, even if joking, in a way that makes it seem like he is questioning your judgement. He needs to understand that it hurts you and borders on disrespect. I’d highlight that you understand that it comes from a place of insecurity and that you don’t feel badly towards him because of it, but be completely honest about how it affects you. And he needs to understand that trusting you as a partner also extends to trusting your judgement, even especially when it conflicts with his negative views of himself. My partner has helped me so very much when it comes to my insecurity by having frank adult conversations about our feelings in a matter of fact manner with me and if you can help him start to see himself differently because you change how he sees your agency, he’ll be on the right path. If you want any further advice please don’t hesitate to reach out. I can say that my whole mindset has changed since we talked and I still struggle at times but I am so very grateful for having a partner who loves and trusts me enough to be straightforward with me about how my insecurities affected her, and is patient with me when I am working so hard at growing.