The "Game Rating" estimated elo is just an estimate of how well you played during that particular game. It fluctuates wildly and is not an accurate description of how you play overall.
ELO Deflation is wild these days
The so called "Game rating" shows the temperature on Venus when you try to find out the temperature in your room, so to speak
i player this game against a another 400 elo player (ok they are a little lower than me) and the game review literally called us 1000s. what is happening going on(you might need to download the image or because it is too low res)

here's the game if anyone wants to see it (they resigned btw)
yeah the elo deflation(anti inflation) is CRAZY