Make sure model is infeasible

Author: ValentinKaisermayer

src/Infeasibility/analyze.jl

@@ -219,7 +219,8 @@ function _analyze_native_iis(model::MOI.ModelLike, optimizer)
     end
     index_map = MOI.copy_to(solver, model)
     reverse_map = _reverse_index_map(index_map)
-
+    
+    MOI.optimize!(solver) # make sure model is infeasible 
     MOI.compute_conflict!(solver)
 
     status = MOI.get(solver, MOI.ConflictStatus())