Dad not bonding with second baby. 😢

So hubby and I just had our second baby. Our oldest is 18 months and new baby is a month old. I’ve noticed he is having trouble bonding with our baby. He doesn’t ever ask to hold her. The only time he does is when I ask him to. He changes diapers and stuff and helps/plays with our oldest daughter plenty so it’s not a matter of laziness. He says it’s because I’m nursing our youngest so she needs me more right now but I’m not buying it. There’s hours in between feeds when she just sleeps and he could get some cuddles in. I worry he’ll always favor our oldest if he doesn’t make an effort to establish that bond with our baby too. I already feel bonded to both our girls equally. Have any of y’all experienced your children’s father having trouble or taking longer to bond with a new baby? I’ve tried talking to him about it and he seems to get annoyed and think I’m calling him a bad dad but that’s not the case at all. When she cries he doesn’t have very much patience at all and gets super frustrated and wants to give her right back to me. I don’t remember him being this way with our oldest. Anyway, I just need advice. What can I do to help them establish that bond? He’s so close with our oldest. They’re seriously best buds.