The S&P index moved up to a high of 4322.62 today.
That high price move between the 61.8% retracement of the move down from the January 2022 high to the low reached in October 2022 at 4311.11, and the swing high going back to August 2022 at 4225.28. The inability to extend above those levels has led to some back backtracking. The low corrective price extended down to 4308.08 so far but is currently trading back higher at 4317.17.
Buyers are trying to keep the momentum going, but there are also good reasons for sellers to lean, as risk can be defined and limited against the aforementioned resistance levels. Traders who want to try and pick a top can always stop out on a break higher.