Solved

Car Points Reset!!???

So, i won the constructors' championship and new season started. 
Now my car points are same like 3 seasons before! 
wtf happened?

I was 1st team and now i am last! wtf?

Hi George after each season car design points are reset so each team has a fair chance of competing. So all teams start from scratch! 

Hi George, your car design is completely reset when switching leagues. It's a measure taken to discourage players to hop from league to league.

However, I can understand your frustration in this, especially when you've won championships before, so I've restored what was nearly all of your design progress.

BUt wait a minute guys, i didnt change any league. I am in the same league all seasons.
After what happened i had to change league because the other teams' points where not reset..

Why wouldn't it be? I can see their next season designs have been applied to their cars and now it is the current season design.

my car has been reset and it made me worse than the other teams

1 team is leading in braking and fuel economy 
another team has cooling and downforce
another team has acceleration  handling and reliability 
and i have tyres only

how is this fair 

Other players may have hired multiple Chief Designers to contribute to the new season car design.