Issue with updating phased rollout percentage through API

The interface error from the document https://developer.samsung.com/galaxy-store/galaxy-store-developer-api/content-publish-api/update-staged-rollout-rate.html is: {"from":"seller","body":{"resultCode":"9000","resultMessage":"Internal Server Error"},"message":"Request failed with status code 500"}. Now I want to change the staged rollout percentage for an app with the status “SALE”. The input parameters are appStatus set to “SALE”, function filled with “ENABLE_ROLLOUT”, and rolloutRate set to 4. I received this error.

Hello 3068305697,

The staged rollout API not working for an app that is for sale is a known issue.

Please note that this is not the correct forum for reporting bugs. If you have not done so already, contact the Seller Portal team to report this issue: from Seller Portal, click Help > Contact us, then click Contact us at the Customer Center (near the bottom of the page). If a pop-up with “Did you mean samsung.com?” appears, close the pop-up.

The interface error from the document Update Staged Rollout Rate | Samsung Developer is: {“errorCode”:“400”,“errorMessage”:“update rate fail: The rollout rate cannot be set to a value smaller than the previous setting value”,“errorSubCode”:“10015”,“success”:false}
but this package is new