diff --git a/src/lte/model/pf-ff-mac-scheduler.cc b/src/lte/model/pf-ff-mac-scheduler.cc
index 167263211..029a61b0a 100644
--- a/src/lte/model/pf-ff-mac-scheduler.cc
+++ b/src/lte/model/pf-ff-mac-scheduler.cc
@@ -1340,7 +1340,7 @@ PfFfMacScheduler::DoSchedUlTriggerReq (const struct FfMacSchedSapProvider::Sched
   do
     {
       std::set <uint16_t>::iterator itRnti = rntiAllocated.find ((*it).first);
-      if (itRnti!=rntiAllocated.end ())
+      if ((itRnti!=rntiAllocated.end ())||((*it).second == 0))
         {
           // UE already allocated for UL-HARQ -> skip it
           it++;
diff --git a/src/lte/model/rr-ff-mac-scheduler.cc b/src/lte/model/rr-ff-mac-scheduler.cc
index 1539bea61..b4d40e350 100644
--- a/src/lte/model/rr-ff-mac-scheduler.cc
+++ b/src/lte/model/rr-ff-mac-scheduler.cc
@@ -1177,7 +1177,7 @@ RrFfMacScheduler::DoSchedUlTriggerReq (const struct FfMacSchedSapProvider::Sched
   do
     {
       std::set <uint16_t>::iterator itRnti = rntiAllocated.find ((*it).first);
-      if (itRnti!=rntiAllocated.end ())
+      if ((itRnti!=rntiAllocated.end ())||((*it).second == 0))
         {
           // UE already allocated for UL-HARQ -> skip it
           it++;