Engineer Specialist Repair Vehicle

The engineer specialist 3rd challenge of "repair vehicles in a match" for 1,000 points is bugging out for me. One mission I received zero points for my repairs. The next mission I got around 250 and it showed up. The follow up mission I got about 850 points, but when I looked at the challenge again it had reset to zero.

Are the entire Engineer Specialist challenges just plagued, as I had issues with the aid in aircraft destruction as well.