Tributary Placement Problem’s

Hello. I´m trying to place the tributary inflows between two specified elevations. In the option “Tributary Placement [PTRC]” I select “SPECIFY” and define the segment [ITR], the Top [ELTRT] and the Botton [ ELTRB] elevations for each tributary. The problem is that all tributaries are incorporated from the beginning of the simulation, regardless of the elevation defined for each tributary. What is the problem? Do I need to select some other option? Regards