I booked a flight with AA flight number that was operated by BA. I didn't get any avios, and after filing a missing avios claim on the website, I got an email response that I'm not qualified for avios and tier points.
Since it's a premium economy flight, and I did get avios and tier points for the other legs on the same trip, the only reason I can think of is the fact that's it's an AA flight operated by BA.
That doesn't make sense to me, but T&C of such programs rarely do. Is this in fact the reason? Maybe an error on BA's part?

Thanks a lot.