I am not sure why the Current Period Start isn't showing?
Go to Solution.
In the Time settings, is the Current Period set? Instead of using CurrentPeriodStart(), you might want to use Start() which is the first day of that time period (which is month in this case).
View solution in original post
@Csta Try using CURRENTPERIODSTART() = START()
first check your format setting by toggling to blue print view. change it to DATE format.