why ausolve does not support material model for debris flow.

Hello experts I am working on debris flow simulation with dam break condition. I tried first with simply water than my fluid (debris). There are few doubts to understand 

1. I defined the air-water multiphase with outlet at downstream side but in the post processing my flow does leave the channel, or it was reversible type when i checked log file. It was showing following warning after each iteration how to fix this issue.

WARNING: inflow at outflow boundary: Outlet 1 (mass/time: in=-7.282052e-01, out=7.282179e-01)

2. when I replaced water to debris acusove exit with following error 

evelset stagger "levelset":
acuSolve: No of res/lhs formations = 5 5
acuSolve: Elem.Form CPU/Elapse time= 7.970300e+01 3.038300e+01 Sec
acuSolve: Solution CPU/Elapse time= 1.337500e+01 4.056000e+00 Sec
acuSolve: Redistancing stagger "redistancing":
acuSolve: No of res/lhs formations = 20 20
acuSolve: Elem.Form CPU/Elapse time= 3.071870e+02 1.394540e+02 Sec
acuSolve: Solution CPU/Elapse time= 8.492200e+01 2.624600e+01 Sec
acuSolve: LnSlv. (host) Elapse time= 2.396200e+02 Sec
acuSolve: Total CPU/Elapse time = 4.360015e+03 1.052095e+03 Sec
acuSolve: Total Memory Usage = 1.512000e+03 Mbytes
acuRun: -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-
acuTrans: *** ASSERTION in Function <adbInitLog> File <adbInitOut.c> Line <5688>
acuTrans: *** Unrecognized log item
acuRun: -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-
acuRun: "C:/Program Files/Altair/2022.1/hwcfdsolvers/acusolve/win64/bin/acuTrans".exe -pb Air-debris_simulation -to cgns -out -run 0 -ts L -v 1
acuTrans: *** ASSERTION in Function <adbInitLog> File <adbInitOut.c> Line <5688>
acuTrans: *** Unrecognized log item
acuRun: *** ERROR: error occurred executing acuTrans
acuRun: Wed Sep 21 18:25:46 2022

I defined my fluid using density and viscosity vs strain rate in material model.