diff --git a/src/constitutive.f90 b/src/constitutive.f90
index cc5c6f3f8..b20d6e65d 100644
--- a/src/constitutive.f90
+++ b/src/constitutive.f90
@@ -863,6 +863,8 @@ subroutine constitutive_collectDotState(S6, FeArray, Fi, FpArray, subdt, subfrac
  plasticityType: select case (phase_plasticity(material_phase(ipc,ip,el)))
 
    case (PLASTICITY_ISOTROPIC_ID) plasticityType
+     of = phasememberAt(ipc,ip,el)
+     instance = phase_plasticityInstance(material_phase(ipc,ip,el))
      call plastic_isotropic_dotState    (Mp,instance,of)
 
    case (PLASTICITY_PHENOPOWERLAW_ID) plasticityType