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

https://www.play-bookmarks.win/rtp-and-house-edge-describe-the-game-s-long-run-maths-a-96-rtp-means-a-4

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, outcomes may differ sharply from the average, so set limits and expect uncertainty.