No achievement

Hey all,
So I am a bit of an achievement hunter type of person. I just raced the Goliath track in the Bentley Continental GT Forza Edition with 5 laps. I came first but did not get the achievement. Is the Bentley not considered a Horizon edition car?
Thanks.

This makes sense now, I did 5 laps in the Alfa Romeo FE and it didn’t work, a few days later I did 3 laps in the Bentley FE and it worked. Must be an error in the achievement description or something. Try just 3 laps.