Sims Rejecting Romance Interactions Regardless of Relationship

Basically what the title says. I'm having this issue in multiple saves. My sims will reject almost ALL romance interactions despite them having a full friendship bar and literally being engaged. Rarely they will flirt autonomously and it will be accepted, but when I go to follow up with another romance interaction, it will be rejected. I've tried "warming them up" by using friendly interactions until the conversation is "pleasant" while they're both flirty and even then it doesn't work. Their sexual orientations both check out; the man is attracted to women and the woman is attracted to men. They all just end in making the conversation awkward and I really don't understand how this is happening because they had a full romance bar last time I played. I didn't start having this issue until after the infants update, though I hadn't played in a while before then so it could've been one previous to that. Before I updated, they would accept every romantic interaction without issue. I do have mods and cc so it's possible this bug comes from one of those, but currently all the ones I'm running are up to date. Has this happened to anyone else? It's really frustrating because I can't move forward with their wedding if they won't even flirt with each other :/.