Galactic Challenge Feat Not Working?

The feat is 'win while using 3 rebel ships' and I have completed the challenge 3 times using the falcon, phantom 2 and ghost but it is still not giving me the feat. I even did it with 4 rebel ships throwing in the y-wing and it did not register? I even finished the battle with 3 rebel ships on the field so im not sure if im missing something?