[screengreen]

I am new to Fluent, and I am modelling an open channel multiphase flow with air and water. https://imgur.com/a/WaOJBWh

Conditions: Transient flow with VOF method, with a mass flow inlet, and pressure outlet at the outlet and open surface. The simulation has worked for 2 different flow rates at 2 different heights. For this particular flow, the initial height is 0.268m at a flow rate of 50.5kg/s. I am trying to initialise the volume of water in the fluid domain at a height of 0.268m by marking the region till a height of 0.268m but all that the wall contours for phases are showing me is this: https://imgur.com/a/P3QJaUS . It should be at the green level for the whole wall. What are the steps to achieve that and what am I doing wrong?