diff --git a/openair3/NAS/NR_UE/5GS/5GMM/MSG/RegistrationAccept.c b/openair3/NAS/NR_UE/5GS/5GMM/MSG/RegistrationAccept.c
index d65d196701..f6b67edb11 100644
--- a/openair3/NAS/NR_UE/5GS/5GMM/MSG/RegistrationAccept.c
+++ b/openair3/NAS/NR_UE/5GS/5GMM/MSG/RegistrationAccept.c
@@ -79,7 +79,6 @@ static int decode_nssai_ie(nr_nas_msg_snssai_t *nssai, uint8_t *num_slices, uint
   const uint8_t *end = buf + length;
   while (buf < end) {
     nr_nas_msg_snssai_t *item = nssai + nssai_cnt;
-    item->sd = 0xffffff;
     const int item_len = *buf++; // Length of S-NSSAI IE item
     switch (item_len) {
       case 1:
@@ -89,31 +88,38 @@ static int decode_nssai_ie(nr_nas_msg_snssai_t *nssai, uint8_t *num_slices, uint
 
       case 2:
         item->sst = *buf++;
-        item->hplmn_sst = *buf++;
+        item->hplmn_sst = malloc_or_fail(sizeof(*item->hplmn_sst));
+        *item->hplmn_sst = *buf++;
         nssai_cnt++;
         break;
 
       case 4:
         item->sst = *buf++;
-        item->sd = 0xffffff & ntoh_int24_buf(buf);
+        item->sd = malloc_or_fail(sizeof(*item->sd));
+        *item->sd = 0xffffff & ntoh_int24_buf(buf);
         buf += 3;
         nssai_cnt++;
         break;
 
       case 5:
         item->sst = *buf++;
-        item->sd = 0xffffff & ntoh_int24_buf(buf);
+        item->sd = malloc_or_fail(sizeof(*item->sd));
+        *item->sd = 0xffffff & ntoh_int24_buf(buf);
         buf += 3;
-        item->hplmn_sst = *buf++;
+        item->hplmn_sst = malloc_or_fail(sizeof(*item->hplmn_sst));
+        *item->hplmn_sst = *buf++;
         nssai_cnt++;
         break;
 
       case 8:
         item->sst = *buf++;
-        item->sd = 0xffffff & ntoh_int24_buf(buf);
+        item->sd = malloc_or_fail(sizeof(*item->sd));
+        *item->sd = 0xffffff & ntoh_int24_buf(buf);
         buf += 3;
-        item->hplmn_sst = *buf++;
-        item->hplmn_sd = 0xffffff & ntoh_int24_buf(buf);
+        item->hplmn_sst = malloc_or_fail(sizeof(*item->hplmn_sst));
+        *item->hplmn_sst = *buf++;
+        item->hplmn_sd = malloc_or_fail(sizeof(*item->hplmn_sd));
+        *item->hplmn_sd = 0xffffff & ntoh_int24_buf(buf);
         buf += 3;
         nssai_cnt++;
         break;
@@ -198,3 +204,21 @@ int encode_registration_accept(const registration_accept_msg *registration_accep
 
   return encoded;
 }
+
+/** Memory management of NAS Registration Accept */
+
+static void free_nssai(nr_nas_msg_snssai_t *msg)
+{
+  free(msg->hplmn_sd);
+  free(msg->hplmn_sst);
+  free(msg->sd);
+}
+
+void free_fgmm_registration_accept(registration_accept_msg *msg)
+{
+  free(msg->guti);
+  for (int i = 0; i < NAS_MAX_NUMBER_SLICES; i++) {
+    free_nssai(&msg->nas_allowed_nssai[i]);
+    free_nssai(&msg->config_nssai[i]);
+  }
+}
diff --git a/openair3/NAS/NR_UE/5GS/5GMM/MSG/RegistrationAccept.h b/openair3/NAS/NR_UE/5GS/5GMM/MSG/RegistrationAccept.h
index 4c50de9384..c373c067fa 100644
--- a/openair3/NAS/NR_UE/5GS/5GMM/MSG/RegistrationAccept.h
+++ b/openair3/NAS/NR_UE/5GS/5GMM/MSG/RegistrationAccept.h
@@ -51,9 +51,9 @@ typedef enum {
 // 9.11.3.37 of 3GPP TS 24.501
 typedef struct {
   int sst;
-  int hplmn_sst;
-  int sd;
-  int hplmn_sd;
+  int *hplmn_sst;
+  int *sd;
+  int *hplmn_sd;
 } nr_nas_msg_snssai_t;
 
 /*
@@ -81,4 +81,6 @@ size_t decode_registration_accept(registration_accept_msg *registrationaccept, c
 
 int encode_registration_accept(const registration_accept_msg *registrationaccept, uint8_t *buffer, uint32_t len);
 
+void free_fgmm_registration_accept(registration_accept_msg *msg);
+
 #endif /* ! defined(REGISTRATION_ACCEPT_H_) */
diff --git a/openair3/NAS/NR_UE/nr_nas_msg.c b/openair3/NAS/NR_UE/nr_nas_msg.c
index 5ee233172c..55bad1c2eb 100644
--- a/openair3/NAS/NR_UE/nr_nas_msg.c
+++ b/openair3/NAS/NR_UE/nr_nas_msg.c
@@ -1410,11 +1410,14 @@ static void request_default_pdusession(nr_ue_nas_t *nas)
   itti_send_msg_to_task(TASK_NAS_NRUE, nas->UE_id, message_p);
 }
 
-static int get_user_nssai_idx(const nr_nas_msg_snssai_t allowed_nssai[8], const nr_ue_nas_t *nas)
+static int get_user_nssai_idx(const nr_nas_msg_snssai_t allowed_nssai[NAS_MAX_NUMBER_SLICES], const nr_ue_nas_t *nas)
 {
-  for (int i = 0; i < 8; i++) {
+  for (int i = 0; i < NAS_MAX_NUMBER_SLICES; i++) {
     const nr_nas_msg_snssai_t *nssai = allowed_nssai + i;
-    if ((nas->uicc->nssai_sst == nssai->sst) && (nas->uicc->nssai_sd == nssai->sd))
+    /* If it was received in Registration Accept, check the SD
+       in the stored Allowed N-SSAI, else, consider the SD valid */
+    bool sd_match = !nssai->sd || (nas->uicc->nssai_sd == *nssai->sd);
+    if ((nas->uicc->nssai_sst == nssai->sst) && sd_match)
       return i;
   }
   return -1;
@@ -1476,7 +1479,6 @@ static void handle_registration_accept(nr_ue_nas_t *nas, const uint8_t *pdu_buff
   // process GUTI
   if (msg.guti) {
     process_guti(&msg.guti->guti, nas);
-    free(msg.guti);
   } else {
     LOG_W(NAS, "no GUTI in registration accept\n");
   }
@@ -1495,6 +1497,8 @@ static void handle_registration_accept(nr_ue_nas_t *nas, const uint8_t *pdu_buff
   } else {
     request_default_pdusession(nas);
   }
+  // Free local message after processing
+  free_fgmm_registration_accept(&msg);
 }
 
 /* 3GPP TS 24.008 10.5.7.3 GPRS Timer */