RTP is a long-run average, not a session promise: 96% RTP means a 4% house edge...

https://emilianosexcellentcolumn.scriblorax.com/posts/if-house-edge-is-fixed-what-can-i-control-as-a-player

RTP is a long-run average, not a session promise: 96% RTP means a 4% house edge over time. Volatility describes how uneven results can be. In a short session, you can finish well above or below the average.