WBS disappeared after entering data in primary cost

Hi all,

I used transaction cj40 to enter a value for a WBS element. For example, select TST-NOV-130001-DE-02-1, go to Primary Cost and enter a value. After that, when I saved the data, the return screen for cj40 displayed the wrong WBS hierarchy as in the last screenshot.

Do you have any ideas about this issue? Thank you very much