No way for a 4.5 l Sensor!

Contrary to what is written in the presentation and suggesting that this seal may equally be used for a sensor with a capacity of 4.5 liters or 6 liters, the gasket does not seal the casserole for a capacity of 4.5 liters (I do not know what it is for 6 liters). I ended up with an unusable Sensor as pressure cooker: as the seal is the same brand as my pot, I guess it's a way to get me to buy a newer (mine having a good ten years and having offered me any satisfaction until the seal abyss). My confidence in the brand being shaken, I do not think redeem Seb ...
Obviously, the responsibility for this disappointment in Amazon is absolutely not in question.