I get the following error: "Could not change the sales price. You can change within the range between: up to 50% lower - up to 100% higher than the previous sales price before the change."

To prevent sellers from providing incorrect price amounts and protect them from their mistake, Coupang limits price modification within to the given range.

If you need to adjust your prices by a big margin all at once, please use [Change Price by Item API] to set "forceSalePriceUpdate" to 'True'.