Change Object from Multi List Selection

I want to change one Attribute of all selected Objects from my MultiList. If I run this code, the only object which will be changed is the first one. If I select more then the script trys to change the first object multiple time. I think the problem is in the loop, but I just cannot find it. Does someone know a solution?

void changeObj(DB db)
{
    Buffer IDtextbuf = create()
    Buffer b = create
    Module m = current
    string objectID
    string Delimiter     = ", "   
    string destID
    string s = ""   
    string IDtext=get(dbeIDtext)
    Object o = current  

for nm in dbeModuleList do
{
    destID = o."Change Request"
    IDtextbuf = destID
    Regexp reg = regexp IDtext
    objectID = o."Object ID"

    if (reg IDtextbuf)
    {
        print("Object " objectID " already contains " IDtext"!\n")
    }
    else
    {

    if (destID == "")
    {
        b= IDtext
    }
    else
    {
        b += destID
        b += Delimiter
        b += IDtext
    }
    destID = stringOf(b)
    o."Change Request" = destID
    delete(b)

}       
}
}