fixup! fix: unhack observed in process_SciMLProblem

Author: AayushSabharwal

src/systems/problem_utils.jl

@@ -756,7 +756,11 @@ function process_SciMLProblem(
     cmap, cs = get_cmap(sys)
     kwargs = NamedTuple(kwargs)
 
-    obs, eqs = unhack_observed(observed(sys), eqs)
+    if eltype(eqs) <: Equation
+        obs, eqs = unhack_observed(observed(sys), eqs)
+    else
+        obs, _ = unhack_observed(observed(sys), Equation[x for x in eqs if x isa Equation])
+    end
     is_time_dependent(sys) || add_observed_equations!(u0map, obs)
 
     op, missing_unknowns, missing_pars = build_operating_point!(sys,