Replace with string not working

General
1

I have this line of code that is suddenly not working.
fa is a folderitem that is inside/under thcoll.

Dim fs As String = Replace(Fa.NativePath, IniHerd.ThColl.NativePath, "")

It used to remove that portion of thcoll from fa. Now it just leaves it.
Suggestions?
If it could be OS it is Mac. Current XOJO

2

It would greatly help to know the actual content of fa.nativepath and IniHerd.ThColl.NativePath.

3

FA.NATIVEPATH cannot be changed… it is READONLY

Look at PARENT and CHILD properties

4

Sorry Michel. I had the wrong property