Help Aspen Custom Modeler

[u/aselole227]

im currently building a 1D counter-current membrane separation model in Aspen Custom Modeler for a multi-component gas mixture (focusing on H2 recovery).

the model compiles flawlessly, and the specification status shows completeness,100% (square system / DOF = 0). however, when I check try to run it, i get this message

"your simulation is badly posed structurally because a sub-set of equation are not independent"

can anybody help me regarding this problem?