diff --git a/srsgnb/hdr/stack/ngap/ngap.h b/srsgnb/hdr/stack/ngap/ngap.h
index 6c8a2d12f..65700a5b3 100644
--- a/srsgnb/hdr/stack/ngap/ngap.h
+++ b/srsgnb/hdr/stack/ngap/ngap.h
@@ -154,7 +154,7 @@ private:
 
     ue*            find_ue_rnti(uint16_t rnti);
     ue*            find_ue_gnbid(uint32_t gnbid);
-    ue*            find_ue_amfid(uint32_t amfid);
+    ue*            find_ue_amfid(uint64_t amfid);
     ue*            add_user(value_type user);
     void           erase(ue* ue_ptr);
     iterator       begin() { return users.begin(); }
@@ -190,7 +190,7 @@ private:
     ngap* ngap_ptr = nullptr;
   };
 
-  ue* handle_ngapmsg_ue_id(uint32_t gnb_id, uint32_t amf_id);
+  ue* handle_ngapmsg_ue_id(uint32_t gnb_id, uint64_t amf_id);
 
   srsran::proc_t<ng_setup_proc_t> ngsetup_proc;
 
diff --git a/srsgnb/hdr/stack/ngap/ngap_ue_utils.h b/srsgnb/hdr/stack/ngap/ngap_ue_utils.h
index f0067ef50..a1a455919 100644
--- a/srsgnb/hdr/stack/ngap/ngap_ue_utils.h
+++ b/srsgnb/hdr/stack/ngap/ngap_ue_utils.h
@@ -24,7 +24,7 @@ struct ngap_ue_ctxt_t {
 
   uint16_t                   rnti           = SRSRAN_INVALID_RNTI;
   uint32_t                   ran_ue_ngap_id = invalid_gnb_id;
-  srsran::optional<uint32_t> amf_ue_ngap_id;
+  srsran::optional<uint64_t> amf_ue_ngap_id;
   uint32_t                   gnb_cc_idx     = 0;
   struct timeval             init_timestamp = {};
 
diff --git a/srsgnb/src/stack/ngap/ngap.cc b/srsgnb/src/stack/ngap/ngap.cc
index b6e15cb0d..423af12ab 100644
--- a/srsgnb/src/stack/ngap/ngap.cc
+++ b/srsgnb/src/stack/ngap/ngap.cc
@@ -302,7 +302,7 @@ ngap::ue* ngap::user_list::find_ue_gnbid(uint32_t gnbid)
   return (it != users.end()) ? it->second.get() : nullptr;
 }
 
-ngap::ue* ngap::user_list::find_ue_amfid(uint32_t amfid)
+ngap::ue* ngap::user_list::find_ue_amfid(uint64_t amfid)
 {
   auto it = std::find_if(users.begin(), users.end(), [amfid](const user_list::pair_type& v) {
     return v.second->ctxt.amf_ue_ngap_id == amfid;
@@ -758,7 +758,7 @@ bool ngap::sctp_send_ngap_pdu(const asn1::ngap::ngap_pdu_c& tx_pdu, uint32_t rnt
  * @param amf_id amf_ue_ngap_id value stored in NGAP message
  * @return pointer to user if it has been found
  */
-ngap::ue* ngap::handle_ngapmsg_ue_id(uint32_t gnb_id, uint32_t amf_id)
+ngap::ue* ngap::handle_ngapmsg_ue_id(uint32_t gnb_id, uint64_t amf_id)
 {
   ue*     user_ptr     = users.find_ue_gnbid(gnb_id);
   ue*     user_amf_ptr = nullptr;