diff --git a/openair2/LAYER2/NR_MAC_UE/config_ue.c b/openair2/LAYER2/NR_MAC_UE/config_ue.c
index cef13b87fb..6702897c09 100644
--- a/openair2/LAYER2/NR_MAC_UE/config_ue.c
+++ b/openair2/LAYER2/NR_MAC_UE/config_ue.c
@@ -660,6 +660,8 @@ int nr_rrc_mac_config_req_ue(
       if (mac->scc_SIB->tdd_UL_DL_ConfigurationCommon->pattern1.nrofUplinkSymbols>0) num_slots_ul++;
       LOG_I(MAC, "Initializing ul_config_request. num_slots_ul = %d\n", num_slots_ul);
       mac->ul_config_request = (fapi_nr_ul_config_request_t *)calloc(num_slots_ul, sizeof(fapi_nr_ul_config_request_t));
+      for (int i=0; i<num_slots_ul; i++)
+        pthread_mutex_init(&(mac->ul_config_request[i].mutex_ul_config), NULL);
       // Setup the SSB to Rach Occasions mapping according to the config
       build_ssb_to_ro_map(mac);//->scc, mac->phy_config.config_req.cell_config.frame_duplex_type);
       mac->if_module->phy_config_request(&mac->phy_config);
diff --git a/openair2/LAYER2/NR_MAC_UE/nr_ue_scheduler.c b/openair2/LAYER2/NR_MAC_UE/nr_ue_scheduler.c
index 6536bf704a..91ac5a7422 100644
--- a/openair2/LAYER2/NR_MAC_UE/nr_ue_scheduler.c
+++ b/openair2/LAYER2/NR_MAC_UE/nr_ue_scheduler.c
@@ -948,7 +948,6 @@ NR_UE_L2_STATE_t nr_ue_scheduler(nr_downlink_indication_t *dl_info, nr_uplink_in
     if (ul_config){
       pthread_mutex_lock(&ul_config->mutex_ul_config);
       if ((ul_info->slot_tx == ul_config->slot && ul_info->frame_tx == ul_config->sfn) && ul_config->number_pdus > 0){
-        pthread_mutex_unlock(&ul_config->mutex_ul_config);
 
         LOG_D(NR_MAC, "In %s:[%d.%d]: number of UL PDUs: %d with UL transmission in [%d.%d]\n", __FUNCTION__, frame_tx, slot_tx, ul_config->number_pdus, ul_config->sfn, ul_config->slot);
 
@@ -959,7 +958,6 @@ NR_UE_L2_STATE_t nr_ue_scheduler(nr_downlink_indication_t *dl_info, nr_uplink_in
         tx_req.sfn = frame_tx;
         tx_req.number_of_pdus = 0;
 
-        pthread_mutex_lock(&ul_config->mutex_ul_config);
         for (int j = 0; j < ul_config->number_pdus; j++) {
           uint8_t *ulsch_input_buffer = &(ulsch_input_buffer_array[tx_req.number_of_pdus][MAX_ULSCH_PAYLOAD_BYTES]);
 
@@ -1020,16 +1018,15 @@ NR_UE_L2_STATE_t nr_ue_scheduler(nr_downlink_indication_t *dl_info, nr_uplink_in
             }
           }
         }
-        pthread_mutex_unlock(&ul_config->mutex_ul_config);
+        pthread_mutex_unlock(&ul_config->mutex_ul_config); // avoid double lock
 
         fill_scheduled_response(&scheduled_response, NULL, ul_config, &tx_req, mod_id, cc_id, rx_frame, rx_slot, ul_info->thread_id);
         if(mac->if_module != NULL && mac->if_module->scheduled_response != NULL){
           mac->if_module->scheduled_response(&scheduled_response);
         }
+        pthread_mutex_lock(&ul_config->mutex_ul_config);
       }
-      else {
-        pthread_mutex_unlock(&ul_config->mutex_ul_config);
-      }
+      pthread_mutex_unlock(&ul_config->mutex_ul_config);
     }
   }