Air China -- removing miles from account?

I accidentally credited some longhaul CA flights to Phoenix Miles last year. I emailed ffp@airchina.com and they emailed back to tsay they can't remove them from my account (as I want to credit elsewhere). I'm sure I have had other airlines do this -- any suggestions as to how I might succeed? I'd call, but whenever I call they say I have to email if it's about PhoenixMiles.

Thanks.