How do I handle a 31M friend (who I used to date) joking about me (32F) being with another male friend (28M) who’s like a brother to me?

I’m a 32F. I have two close male friends:

• Friend A (31M) — we used to be in a relationship. It didn’t work out the way either of us planned, but we stayed close. We still joke around a lot, and I’ll sometimes joke about “taking a flight to see him,” which used to be a bit but now feels more real because of our history.
• Friend B (28M) — genuinely like a brother to me. Zero romantic vibe. I’ve even had to set boundaries with him in the past because he said some out‑of‑line things, so I’m very clear that nothing is happening there.

Here’s the issue:
Even after I told Friend A that Friend B sees me like a sister and there’s nothing romantic there, Friend A keeps making jokes about Friend B being “my boyfriend” or implying something is going on.

It used to be funny, but now it feels weird — especially because of the past between me and Friend A. I don’t know if he’s teasing, projecting, deflecting, or just stuck in an old joke that doesn’t fit anymore.

I don’t want to make it dramatic or emotional, but the joke is starting to annoy me and I’m not sure how to shut it down or redirect it without sounding defensive.

How would you handle this?