Hi Listya,
What kind of the error message you are receiving ?
How you have hidden the field and what is happening, can you please provide more insight on this ? Note 305621 is related to PM, i dont think this will impact on PS.
Below is the screenshot from service, are you checking about this cost element
Just click on the Configuration Icon (right corner with blue/ yellow icon) and you can make the field invisible. This will hide for all users.
Regards
Terence