The Hetumant River in Afghanistan

In the past let's say 2000 years ago. It was called the hetumant river And even before that it was called the setumant or the to wonder river in sanskrit. Today this river is called the helmand and flows through most of Afghanistan, but then it drains into what was once a lake here in iran I don't remember the name of this lake. The past 20 or 30 years this lake has been dry This lake received its water from thehetumant from the helmand river Which is which passes through AfghanistanWhich is controlled by Afghanistan and Afghanistan has dams on this river Now the so iran wants Afghanistan to release sufficient water into systhan