RTP is a game’s theoretical average return over a very large number of plays;...

https://www.bookmarking-online.win/rtp-is-a-long-run-average-not-a-session-forecast-96-rtp-means-a-4-house

RTP is a game’s theoretical average return over a very large number of plays; the house edge is the casino’s corresponding advantage. A 96% RTP means a 4% house edge on average, not a promise about your session