Like thousands of others who had significant score increases from a recent SAT or past PSAT, you probably can understand why they would flag your score based on such a large increase of scores.
What you’re have difficulty understanding (and rightly so) is what all this nonsense about scratch work inconsistencies and similar answers to others is about.
That’s the thing you have to understand. There is no point in trying to understand why ETS is making such absurd accusations. They do it because they have determined to cancel your scores based solely on the fact that they do not believe large score increases are possible in most cases and are using safeguards to protect themselves in case you really do have a valid reason.
Trust me. Been there. Done that.