The fact that the RTP is 97%, for example, does not mean that of every $100 staked, at least $97 will be given back to the same player. You should understand it like this: If you invested $100 in the game and won $200 , then someone had to lose at the same time.
As a player you can never be sure whether you are just unlucky or being scamed...
The RTP result is not visible to players. This could only be assessed by a gambling commission that has access to all of the casino’s data