Bonus Credits?

I just had 988,990 credits, i purchased a car for 73,500 which would have brought me down to 915,490. Then i just had a look at a couple of designs for that car and all of a sudden. I had 1,069,990 credits. I’m just wondering where that extra 154,500 credits suddenly came from?

Are you in a club? You might of earned enough xp to go up a tier on the club ladder. Each tier you go up gifts you credits. Sometimes its delayed and makes it seem like you got credits out of nowhere.